lcd dissamble

EX-1 Direct-View LCD Television Chassis

Circuit Description and Troubleshooting Guide

Training Manual

MODELS: KDL-32VL140 KDL-40W4100 KDL-46W4100 KDL-52W4100 KDL-32XBR6 KDL-40WL140 KDL-46WL140 KDL-52WL140 KDL-37XBR6 KDL-40XBR6 KDL-46XBR6 KDL-52XBR6 KDL-40V4100 KDL-40Z4100 KDL-46Z4100 KDL-52V4100 KDL-40V4150 KDL-46V4100 KDL-42V4100 Course : CTV-45

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Board Layout ......................................................................1152-inch V Series Models .................................................... 14Board Layout ..................................................................... 14

The W Series ................................................................. 1460HZ versus 120HZ TCON ............................................... 1740 and 46-inch Models ...................................................... 18Board Layout ..................................................................... 18

Chapter 3 – Video Process Circuits ................................. 22Overview ........................................................................ 22

V and W Series Video Process Circuits ............................. 22NTSC Tuner Signals ............................................................. 22Composite and Y/C inputs .................................................... 22Component Inputs ................................................................. 22HDMI Inputs .......................................................................... 22PC Input ................................................................................ 23Front End Microprocessor and Decoder ............................... 23Back End Microprocessor ..................................................... 23LCD Panel ............................................................................. 2310-bit Video Processing ........................................................ 25Ethernet Port ......................................................................... 25USB 2.0 Input ........................................................................ 25Digital Media Port .................................................................. 25

Troubleshooting ............................................................. 27No Video ............................................................................ 27Video Distortions ................................................................ 27Troubleshooting Flowcharts ............................................... 27

Chapter 1 – Introduction ..................................................... 1Overview .......................................................................... 1Features .......................................................................... 1

Full HD 1080 Panel .............................................................. 1Motionflow™ ........................................................................ 1Enhanced Cross Media Bar (XMB) ...................................... 1HDMI 1.3 .............................................................................. 2

Consumer Electronics Control (CEC) ..................................... 2xvYCC ..................................................................................... 2Deep Color .............................................................................. 2

Bravia® Sync ....................................................................... 2Advanced Contrast Enhancer (ACE) ................................... 2Digital Media Port ................................................................ 2Digital Media Extender (DMEX) ........................................... 2Interactive Program Guide (IPG) ......................................... 2Digital Living Network Alliance (DLNA) ................................ 24 HDMI Inputs ...................................................................... 2

Chapter 2 – Overall Block Diagrams .................................. 3Overview .......................................................................... 3Overall Block Diagrams ................................................... 3The V Series .................................................................... 3

32/37-inch Models Overall Block Diagram ........................... 4Board Layout ....................................................................... 642-inch Model ...................................................................... 8Board Layout ....................................................................... 840 and 46-inch Models .......................................................11

Table of Contents

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Table of Contents (Continued)Chapter 4 – Audio Process Circuits ................................. 29

Overview ........................................................................ 29General Audio Processing ................................................. 29HDMI .................................................................................. 29USB 2.0 ............................................................................. 29Ethernet (DLNA) ................................................................ 29

Troubleshooting ............................................................. 29

Chapter 5 - Power Supply ................................................. 31Overview ........................................................................ 31

G1D/G2D Power Supplies ................................................. 31Power Factor Control (PFC) ................................................. 31Standby Power Supply .......................................................... 31Main Switching Supply .......................................................... 31

IP5 Power Supply and Inverter .......................................... 33Integrated Lamp Inverter ....................................................... 33

G4 Power Supply ............................................................... 33PFC Output ........................................................................... 33

G5 Power Supply ............................................................... 33Troubleshooting ............................................................. 37

Completely Dead Unit ........................................................ 37Power Supply Shutdown .................................................... 37Power Supply Troubleshooting Flowchart ......................... 37

Chapter 6 - Panel Backlight Circuits ................................ 39Overview ........................................................................ 39

32/37-inch Backlighting ...................................................... 39

Power-Up Sequence ............................................................. 39Inverter Circuit ....................................................................... 39

42-inch Backlighting ........................................................... 4240/46 V and W Series Backlighting ................................... 43

Inverter .................................................................................. 43Balancer ................................................................................ 45

40/46 Z Series Backlighting ............................................... 47All 52-inch Series Backlighting .......................................... 47

G5 Board ............................................................................... 47D4 Board ............................................................................... 47D5 Board ............................................................................... 47

Troubleshooting ............................................................. 50Inverter Failures ................................................................. 50

Inverter Does Not Start ......................................................... 50Inverter Starts and Turns Off ................................................. 50

Dual Inverter Circuits ......................................................... 51Balancer Errors .................................................................. 51

Troubleshooting Flowcharts ........................................... 52Balancer Board Removal ................................................... 52

Chapter 7 – Protect Circuits ............................................. 58Overview ........................................................................ 58

Voltage Protection .............................................................. 58DC Detect (2X) ...................................................................... 58DC Alert (3X) ......................................................................... 58

Backlight Protection ........................................................... 58Inverter Error (6X) ................................................................. 58Balancer Error (13X) ............................................................. 59

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Other Protection ................................................................. 59Temperature (7X) .................................................................. 59Speaker Protect (8X) ............................................................ 59Trident (11X) ......................................................................... 59TCON or HFR (12X 14X) ...................................................... 59

Diagnostics History ........................................................ 61Troubleshooting Flowcharts ........................................... 61Troubleshooting Test Points .......................................... 61

Chapter 8 – Appendix ........................................................ 69Software Updates .......................................................... 69

Why Update? ..................................................................... 69Checking the Version of Software ...................................... 69Performing the Update ....................................................... 71Downloading an Update .................................................... 72

Formatting the USB Device .................................................. 72Installing the File(s) to the USB Device ................................ 72

Updating the Television ...................................................... 73Notification of Update ............................................................ 73FE Micro Update ................................................................... 73BE Micro Update ................................................................... 73Update Completion ............................................................... 73

LCD Panel Troubleshooting ........................................... 76LCD Panel Basics .............................................................. 76Panel Failures .................................................................... 77

Physical Failures ................................................................... 77

TCON Failures ................................................................... 79

Table of Contents (Continued)Troubleshooting a “Dead” TCON .......................................... 80

DLNA Overview ............................................................. 82

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Chapter 1 – Introduction

OverviewThe EX-1 chassis is one of several designs for the 2008 model line of Sony Bravia® LCD televisions. 22 models are available as of this writing ranging from 32” to 52”. The models are grouped in categories beginning with the V series as an introductory product for a full HD 1080 panel. The W series is an intermediate level product and introduces a frame doubling circuit known as Motionflow™ to provide a 120HZ refresh rate. Upgrade level televisions are available in the Z and XBR series models.

NOTE: Although there are 5 XBR models, the 32 and 37-inch models are classified as entry-level models in that they do not contain the features found in the 40, 46, and 52-inch models. When referring to the XBR series, the term “small XBR” and “large XBR” will be used when necessary.

The chassis design revolves around the video processing circuits located on the BU board. It remains relatively the same except for a couple of additional input features and 10-bit video processing found on the upper-end models. The key difference between models is determined by the size of the LCD panel and its manufacturing source. This manual will describe the new circuit features and individually describe the models based on these differences.

FeaturesSeveral new features are introduced in the EX-1 chassis model lineup along with some carryovers from the previous year. The included features will vary based on the model series and will be indicated in the following descriptions:

Full HD 1080 PanelAll models have a 1920 X 1080 native resolution panel. All video signals exit the video process circuits as 1080p 60HZ. The V, W and 32/37XBR6 series utilize an 8-bit panel and video processing while the Z and larger XBR6 models use a 10-bit panel and video processing.

Motionflow™A frame-doubling circuit utilizing proprietary circuitry and algorithms is able to capture and compare the movement from one frame to another. By anticipating the location of a moving object, an additional frame is inserted to increase the frame refresh rate from 60HZ to 120HZ. The result is an exceptionally smooth picture during fast moving objects and scenes. This feature is available on the W, Z, and large XBR6 models.

The customer has the option of changing the settings of the Motion Enhancement and Motion Compensation circuits to smooth the “judder” inherent with 24-frame film-based content or can choose keep the judder for a film-like experience.

Enhanced Cross Media Bar (XMB)A new graphics user interface with rich 3-D graphics allowing the user to customize the setup of the television and to access various adjustments and control of optional devices. Optional external devices can also be detected and displayed. An example would be when a customer plugs in the Bravia Internet Video Link device to access the internet. When the device is detected, additional icons appear in the XMB graphics OSD to allow control of the device. Other optional devices will become available and will be described later.

Chapter 1 - Introdcution

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HDMI 1.3This new version of HDMI introduces several new enhancements and features and the EX-1 chassis supports 3 of the new features.

Consumer Electronics Control (CEC)

A standardized protocol for the control of consumer electronics devices allows for communication and control via the HDMI cable on products that have this feature. Any brand of electronic equipment that is CEC compliant can communicate with another to generate operational commands. The Bravia Sync feature uses the CEC format to control other Sony devices in the system.

xvYCC

The previous color bandwidth limitations applied for compatibility with analog signals are no longer present with digital signals. This allows for 1.8 times more colors.

Deep Color

The previous HDMI specifications limited the RGB sample level to 24-bit. Deep Color expands this up to 48-bit giving the ability to generate a color depth of 2.8 trillion levels.

Bravia® SyncBy utilizing the CEC feature of HDMI 1.3, this feature allows the customer to easily control the various Sony devices within their home entertainment system provided that all of the other devices have this feature included.

Advanced Contrast Enhancer (ACE)By monitoring the overall level of the video signal, the backlights are dynamically controlled and reduced during low light level scenes to enhance the contrast ratio.

Digital Media PortFound on the high-end models, this port allows for the hookup of optional devices that provide an interface with digital media products such as MP3 players and video cameras.

Digital Media Extender (DMEX)A USB 1.0 port is provided to supply a digital connection path to optional modules such as the Bravia Internet Video Link. Selected web sites on the internet can be accessed to play video clips or view local news, traffic, and weather. Devices connected will automatically appear on the XMB menu.

Interactive Program Guide (IPG)An interactive guide is included to provide continuously updated program information at no charge to the customer. The guide (provided by TV Guide) is part of the XMB graphics feature. Program material is updated from the local PBS station when the television is off.

Digital Living Network Alliance (DLNA)An industry standard networking protocol has been developed by leading manufacturers to allow other devices such as a compatible computer to communicate with the television via an Ethernet connection to your home network. This gives the ability to view photos, audio and movie content directly from your computer via the network. If there are any firmware upgrades available for the television, these can be downloaded to the computer and sent directly to the television. The 2008 models in this training manual will only support photos. Music and video media is not supported.

4 HDMI Inputs3 inputs in the rear and one on the side are available for all models. This increases the available inputs to meet the expanding needs of additional devices.

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Chapter 2 – Overall Block Diagrams

OverviewThe EX1 chassis for the 2008 model year is found in 22 models as of this writing. The focal point of this chassis is the video processing circuits located on the BU board. The digital decoder for ATSC signals along with the video process IC remains the same among the models. As one moves from the entry level models to the higher end units, additional features are added to the video process circuits to extend the amount of components that the television can interface with. This includes computer networking and digital media devices. The Z models, along with the 40-inch and up XBR6 series, utilize a 10-bit processing scheme for the LCD panel versus 8-bit for the others.

The major factor separating the various models in the chassis line (other than cosmetics) is panel size along with the original source of the particular LCD panel in that model. These factors are what will determine how the overall block diagrams are segregated. Different panel sizes require different inverter circuits to light the backlights and that includes differences in the power supplies.

The EX1 chassis model lineup is separated into 3 categories:

V Series: These are the introductory level models for those wishing to purchase a full HD 1920 X 1080 panel. It includes all those with a “V” in the model number. Also included in this series is the smaller (32 and 37-inch) XBR6 models.

W Series: Classified as intermediate level units, these models have the 120HZ frame-rate feature (known as MotionFlow™) added to significantly increase the picture quality especially during fast moving scenes. They will have a “W” in the model number.

Z Series: As upper-level models, additional features are included to enhance picture quality. This includes 10-bit LCD panels, 120HZ refresh rate and Wide Color Gamut backlights. Additional features include an Ethernet port, USB 2.0 port and Digital Media port to interface with the customer’s computer and portable devices.

Overall Block DiagramsThe following block diagrams illustrate an overall view of the various circuits used and will be categorized based on panel size and video features. Circuit descriptions will begin with the entry-level V series. There are several similar circuits among the entire model line and these descriptions will be discussed. As the diagrams and descriptions progress up the model line, only the differences in boards and circuitry will be explained. More detailed information for each circuit will appear in the chapters to follow.

The V SeriesThis series consists of the following models:

KDL32VL140

KDL32XBR6

KDL37XBR6

KDL40V4100

KDL40V4150

KDL42V4100

KDL46V4100

KDL52V4100

Chapter 2 - Overall Block Diagrams

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32/37-inch Models Overall Block DiagramFigure 2-1 illustrates an overall block diagram of the models utilizing the 32 and 37-inch LCD panels. This includes the KDL32VL140, KDL32XBR6 and KDL37XBR6.

BU BoardEssentially the “brains” of the system, this board contains all of the input sources for video and audio information along with an on-board ATSC/NTSC combination tuner. It also contains all of the video and audio switching and processing circuits. The front-end (FE) and back-end (BE) microprocessors to control the operation of the television and the video processor functions are located here. All video sources exit the BU board at the native resolution of the LCD panel (1920 X 1080, 60HZ).

The BU board used in these models is specifically configured for the panel types and sizes used. This includes physical, electrical and software configurations. Other models will have additional inputs, different processing schemes and different software which make the BU board specific to the panel type being used.

Note that all input sources are directly connected to the BU board. The past use of separate boards for input switching, tuner, ATSC decoder and side video inputs has all been incorporated onto this single board.

Power SupplyThe 32-inch models contain a G1D board to provide the main operating voltages for the television. It supplies operating voltages to the BU board along with 24VDC for the inverter. The 37-inch model uses a G2D board which is essentially the same except the circuitry is designed to handle the increased current load of the larger panel.

InverterThe inverter is mounted on the left side of the LCD panel (as viewed from the rear) and contains all of the circuitry necessary to generate the 1KVAC operating voltage for the fluorescent backlights. It also contains on-board monitoring circuits to maintain even brightness among the lamps and to notify the BE Micro on the BU board if there is a failure of the inverter or if one or more of the lamps fails to light.

H1 BoardLocated at the top of the unit, the various user input buttons (power, channel and volume up/down, menu and input selection) are located here. The H1 board is mounted to the switch housing and is referred to as the “switch” or “function” block in the service manual.

H2 BoardThe power, timer and standby LED’s are located on this board.

H3 BoardThis board contains the IR receiver LED for the remote control. The same LED also serves as an ambient light sensor. All EX1 chassis models have the ability to automatically adjust the picture brightness and contrast level based on ambient lighting conditions. This feature is turned off by default but can be turned on by the customer in the user menu.

LCD PanelThe 32 and 37-inch panels are full HD (1920 X 1080) utilizing Cold Cathode Fluorescent (CCFL) backlights. There are 16 lamps on the 32-inch and 20 on the 37-inch. The TCON board mounted to the panel is responsible for proper timing and allocation of the RGB data to the correct columns of LCD pixels. White balance and Gamma correction data is also stored on this board. This is why the TCON is not available as a separate service item. If there is a failure in the fluorescent backlights, TCON or the LCD panel, they must be replaced as a single unit.


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A/V DECODERVIDEO PROCESSVIDEO SWITCH

AUDIO PROCESSAUDIO AMPBE MICRO

VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

VIDEO 2

HDMI 2

POWER SUPPLY

SWITCHES LED IRRECEIVER

LCD PANEL

INVERTERTCON

BU

G1D (32")G2D (37")H1 H3 H4

L

R

SIDE INPUTS

FIGURE 2-132/37-INCH OVERALL BLOCK DIAGRAM


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Board LayoutFigure 2-2 shows the board layout for the KDL32XBR6 and Figure 2-3 for the KDL37XBR6. Note that each picture illustrates the unit in assembled form. If the unit requires complete disassembly to replace the LCD panel these pictures provide guidance for the proper placement and routing of the various cables and wire harnesses. It is important that these be routed in their original positions to minimize EMI emissions.

G1D

BUINVERTER

TCON

H4

H3E

H1(FUNCTION

BLOCK)

32XBR6 BOARD LOCATIONSFIGURE 2-232-INCH CIRCUIT BOARD LAYOUT


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FIGURE 2-337-INCH CIRCUIT BOARD LOCATIONS

G2D BU

INVERTER

TCON

H4

H3E

H1(FUNCTION

BLOCK)


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42-inch ModelThe KDL42V4100 model is unique in that the LCD panel configuration is unlike any of the other models. Referring to Figure 2-4, note that this model uses the same GD2 power supply found in the 37-inch model. The G2D board has an extra connector for supplying 24VDC and is used in this model to supply power to the second inverter board.

2 stand-alone inverters are used to drive the fluorescent backlights. Each inverter board drives 10 of the 20 lamps. The inverter on the left side (as viewed from the rear) is the master and the right side the slave. A communications line is connected to the master inverter from the TCON board. Once the TCON receives RGB data from the BU board the inverters will turn on.

Board LayoutFigure 2-5 illustrates the board layout for the KDL42V4100.


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42V4100 OVERALL BLOCK DIAGRAM



VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

VIDEO 2

HDMI 2

POWER SUPPLY


LCD PANEL

INVERTERTCON

BU

G2DH1 H3 H4

L

R

INVERTER

SIDE INPUTS

FIGURE 2-442-INCH V MODEL OVERALL BLOCK DIAGRAM


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G2D

LEFTINVERTER

RIGHTINVERTER

BU

H4

H3

TCON

H1 (FUNCTION

SWITCH)

FIGURE 2-542-INCH V MODEL CIRCUIT BOARD LOCATIONS


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40 and 46-inch ModelsIn Figure 2-6, an overall block diagram indicates the boards used in the 40 and 46-inch models of the V and W series models. These models differ from the previously outlined V models in that a stand-alone inverter circuit is used to power the backlights. The boards that differ from the previously covered models will be explained below:

IP5This board contains the standby power supply, main switching power supply and inverter to drive the backlights. In past years, LCD panels at 40-inches and larger were driven by a stand-alone inverter (or 2 inverters for the 46 and 52-inch models. This year, the 40/46-inch V and W series use a power supply with an integrated inverter to provide the approximately 1KVRMS AC power for the lamps. This circuit will be covered in more detail later in this manual.

BalancerSince the IP5 board provides a common power source for all of the lamps, a circuit must be used to assure that equal current is drawn by each lamp to prevent unequal brightness . This is one of the functions of the balancer. It is also responsible for distributing the high voltage to the lamps and to insure that all lamps are lit up or “struck” at turn-on. The 40-inch panel uses 20 backlights whereas the 46-inch uses 24.

LCD PanelThe 40 and 46-inch LCD panels are also native 1920 X 1080 resolution. Note that this block diagram also applies to the W series models. The only difference is the use of a frame-rate doubling circuit integrated with the TCON board. The V series do not incorporate this and have a panel refresh rate of 60HZ

Board LayoutFigure 2-7 illustrates the board layout for the 40 and 46-inch V series models. The same boards are used for both sizes although the part numbers differ due to software on the BU board and larger balancer for the 46-inch.


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VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

VIDEO 2

HDMI 2

POWER SUPPLY BACKLIGHT INVERTER


LCD PANEL

BALANCER

TCON

HFR*

BU

H1 H3 H4 IP5

*NOT AVAILABLE IN V SERIES

L

R

SIDE INPUTS

FIGURE 2-640 AND 46-INCH V AND W SERIES OVERALL BLOCK DIAGRAM


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TCON

BUIP5

BALANCER

H1(FUNCTION

BLOCK)

H4

H3

FIGURE 2-740 AND 46-INCH V AND W SERIES CIRCUIT BOARD LOCATIONS


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52-inch V Series ModelsFigure 2-8 illustrates the overall block diagram for the 52-inch V series models. Note that this block diagram also includes the W series with the key difference being the use of an integrated frame-rate doubling circuit on the TCON board.

D4 and D5 BoardsThe most significant difference is the use of separate inverter drivers and balancer boards. Due to the longer length of the backlight lamps, exterior current leakage occurs along the length of the lamps and they will tend to darken from one end to the other if a common AC voltage is applied to ionize the gasses. This is solved by using separate inverters to supply out-of-phase AC voltage to the lamps. The D4 and D5 boards output approximately 800VRMS of AC for a differential of 1600 volts. This necessitates the use of a separate power supply located on the G5 board.

Board LayoutFigure 2-9 illustrates the board layout for the 52V series model.

The W SeriesThe following models are included in this series:

KDL40W4100

KDL40WL140

KDL46W4100

KDL46W4150

KDL46WL140

KDL52W4100

KDL52WL140

The major difference between the V and W series (other than cosmetics) is the addition of a high frame-rate circuit within the TCON board. These models utilize 120HZ refresh-rate panels. An additional board labeled as the “Sony Logo Module” contains a row of white LED’s to illuminate the Sony logo on the bottom front of the bezel. This feature can be turned off by the customer in the user menu.

The block diagrams illustrated in Figures 2-6 through 2-8 are drawn to pertain to both the V and W series models with the differences noted in the diagrams.


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VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

VIDEO 2

HDMI 2

POWER SUPPLY

UPPER RIGHT

BALANCER

BU

L

R

LCD PANEL

TCONHFR*

*NOT AVAILABLE IN V SERIES

G5

UPPER LEFT

BALANCER

SWITCHES

H1

LED

H3

IRRECEIVER

H4

SONY LOGO

MODULE(W SERIES

ONLY)

INVERTER

D4

INVERTER

D5SIDE INPUTS

LOWER LEFT

BALANCER

LOWER RIGHT

BALANCER

FIGURE 2-852-INCH V AND W SERIES OVERALL BLOCK DIAGRAM


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G5

D4

D5

UB

UPPER LEFT

BALANCER

TCON

H1(SWITCH UNIT)

H4

H3E

UPPER RIGHT

BALANCER

LOWER RIGHT

BALANCER

LOWER LEFT

BALANCER

FIGURE 2-952-INCH V AND W SERIES CIRCUIT BOARD LOCATIONS


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60HZ versus 120HZ TCONTCON boards containing the high frame-rate Motionflow™ feature are easily distinguished by appearance. Figure 2-10 illustrates this. 60HZ TCON boards are smaller in size and the LVDS cable plugs into the bottom of the board. The 120HZ TCON board are longer horizontally and the LVDS cable plugs into the right side.

60HZ TCON

120HZ TCON

FIGURE 2-1060HZ VS 120HZ TCON


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The Z and Large XBR SeriesThese are the top-of-the-line models in this chassis series. The following models are included:

KDL40Z4100 (available in black or silver trim)

KDL40XBR6

KDL46Z4100 (available in black or silver trim)

KDL46XBR6

KDL52XBR6

Note that the Z series is not available in a 52-inch size.

40 and 46-inch ModelsAn overall block diagram of the 40 and 46-inch models in the Z series is shown in Figure 2-11. There are a couple of differences from the V and W series layout and will be explained below.

G4 BoardUnlike the V and W series which use an integrated power supply and backlight inverter on the IP5 board, the Z series contains a G4 board to generate the operating and standby voltages consistent with many previous designs.

D3 BoardThe D3 board is a stand-alone inverter supplying approximately 1KVRMS of AC voltage for the panel backlights. It also contains on-board voltage monitoring for excessively low or high backlight voltage along with over-current monitoring. If a problem occurs in any of these circuits the unit will be told to shut down for protection.

BU BoardAlthough virtually identical to the BU board used in the V and W series

models, the following feature enhancements are included:

10-Bit Panel Processing: The RGB data exiting the board via the LVDS cable is 10-bit versus 8-bit. This increases the color depth from 256 to 1,024.

Digital Media Port: Allows the use of special adapters to integrate portable digital media devices such as camcorders and MP3 players.

Ethernet Port: Allows connection to a DLNA compliant server or devices for media file viewing.

USB2.0 Port: MP3 audio files and JPG photos can be directly input to the television for viewing and listening.

Board LayoutFigure 2-12 illustrates the board layout for the 40 and 46-inch Z series models. The picture is of the 40-inch model. The 46-inch uses the same board layout but they are spaced further apart due to the larger size of the panel.

52XBR ModelFigure 2-13 contains a layout of the overall block diagram used in the KDL52XBR6 model. Note the similarity with the 52-inch models for the V and W series with the exception of enhancements to the BU board as listed above in the 40/46Z and XBR models. The board layout for this model is the same as the 52W4100 shown in Figure 2-9.


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VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

VIDEO 2

HDMI 2

POWER SUPPLY


LCD PANEL

BALANCER

TCON

HFR

BU

H1 H3 H4G4 (Z SERIES)G6 (XBR SERIES)

L

R

INVERTER

D3

USB 2.0

DIGITAL MEDIA PORT

SONY LOGO

MODULE

ETHERNET

SIDE INPUTS

AWF

SUB-WOOFER

DRIVE

XBR SERIES ONLY

FIGURE 2-1140 AND 46-INCH Z SERIES OVERALL BLOCK DIAGRAM


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BALANCER

TCON

G4

D3

BU

H4

H3

H1 (FUNCTION BUTTONS)

FIGURE 2-1240 AND 46-INCH Z SERIES CIRCUIT BOARD LOCATIONS


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VIDEO 1

COMPONENT 1

RF

VIDEO 3

COMPONENT 2

HDMI 1

HDMI 3

HDMI 4

DVI AUDIO

PC HD15

L/R AUDIO OUT

OPTICAL OUT

USB 1.1

USB 2.0

VIDEO 2

HDMI 2

POWER SUPPLY

UPPERRIGHT

BALANCER

BU

L

R

LCD PANEL

TCONHFR

G5

UPPERLEFT

BALANCER

SWITCHES

H1

LED

H3

IRRECEIVER

H4

SONY LOGO

MODULE

INVERTER

D4

INVERTER

D5

DIGITAL MEDIA PORT

SIDE INPUTS

LOWERLEFT

BALANCER

LOWERRIGHT

BALANCER

ETHERNET

AWF

SUB-WOOFER

DRIVE

FIGURE 2-1352XBR6 OVERALL BLOCK DIAGRAM

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Chapter 3 – Video Process Circuits

OverviewThe video process circuits in the EX1 chassis has achieved yet another reduction in the number of boards required. All of the input switching and processing is accomplished on a single BU board. Even the side video inputs have become part of this board. This significantly affects troubleshooting and parts replacement since the main goal of locating video failures is to determine if the problem is located on the BU board or the LCD panel and TCON board.

The BU board is the one common element among the various models of the EX1 chassis and most of the features located on this board are common. There are added circuits and functions as we move up the model line from introductory to upper level. This applies to the BU board and the TCON board. This chapter will discuss the operation of the video process circuits and outlines the differences encountered between the various models.

V and W Series Video Process CircuitsReferring to Figure 3-1 a simplified block diagram of the circuitry to select and process all video signals is shown. The ATSC/NTSC combination tuner is mounted directly on the BU board. All external input sources are also mounted directly on the board. Descriptions for each of the major components and functions are as follows:

NTSC Tuner Signals

Signals received via NTSC tuner sources are demodulated within the tuner and selected by video switch IC1301. The video signal is then sent to video signal processor IC4700 (Trident). The 480i resolution is processed and up-scaled to 1080p 60HZ for distribution to the LCD panel TCON.

Note that IC1301 has a main and sub video path exiting. All of the models have picture-and-picture capability albeit with limited functionality. When the P&P mode is engaged, only tuner sources are available in the sub-

picture frame. This includes ATSC and NTSC sources. The sub-picture will appear on the right side and is approximately one-half the size of the main picture. Since there is only one tuner in the unit, the input for the main picture will automatically switch to one of the external inputs. Which input is dependent on how the inputs were assigned in the customer setup mode. If all inputs are set for auto-detect, the HDMI 1 input will appear by default. If any other input was set to “always” it will go that input. The main and sub pictures are not scalable.

Composite and Y/C inputs

Only the Video 1 input contains both a composite and Y/C jack. These sources are selected by IC1301 and routed to IC4700 for processing and up-scaling to 1080p 60HZ.

Component Inputs

There are 2 Y/Pb/Pr component inputs on this chassis. They are directly selected by IC4700. All HD formats up to 1080p 60HZ are supported except for 24P content. 24p is only supported via the HDMI inputs.

HDMI Inputs

HDMI input selection is performed by IC5200 and sends the selected input to IC4700. Each HDMI input has its own EDID information stored within a NVM IC. The following IC’s (not shown) are attached to each input:

HDMI 1: IC5101

HDMI 2: IC5191

HDMI 3: IC5131

HDMI 4: IC6161

Chapter 3 - Video Process

CTV-45 23

USB1.1 (DMEX)

This USB input is labeled “DMEX” (Digital Media Extender) on the rear of the unit. If the customer chooses to purchase the optional Bravia Internet Video Link box to access the internet, this port will provide 2-way communication with that device and links with the customer GUI interface. This port is also used to input software upgrades to the television via USB storage devices.

PC Input

Analog RGB input from a PC can be connected to the HD15 connector. The video process circuits will support conventional resolutions from 640 X 480 VGA up to 1920 X 1080 HD. EDID information for the PC HD material is contained within NVM IC5000.

Front End Microprocessor and Decoder

IC7000 decodes the MPEG2 compressed ATSC signals received by the tuner and separates the video and audio content. This IC is also responsible for interface control of the video to IC4700. Customer menu graphics are generated within IC7000.

Back End Microprocessor

IC3001 controls the operation of the unit and provides a user interface. It also monitors key areas of the television for voltage, temperature and speaker protection to turn the unit off if a problem is detected. Another function of IC3001 is to control IC4700 and how it handles the various formats of video signals received by the unit.

LCD Panel

The LCD panel receives the 8-bit RGB video data from the BU board via a Low Voltage Differential Signaling (LVDS) cable. IC4700 contains the LVDS transmitter within and transmits a video resolution of 1920 X 1080 60HZ to match the native resolution of the panel.

The LVDS data is transmitted to the TCON board where an LVDS receiver is located. The LVDS receiver returns the serialized data to its original 8-bit parallel RGB format. In the V series models the panel has a refresh rate of 60HZ. The RGB data is timed and allocated to the proper column drivers for the LCD pixels to produce a picture. White balancing and gamma correction are also performed to compensate for variances in the LD panel.

The W series models use a TCON board with an additional circuit to double the 60HZ refresh rate to 120HZ. This is a very sophisticated circuit that can compare a previous and future frame to the current one and calculate the motion of objects within each frame in order to generate the additional frames with a with exceptionally smooth movement.


CTV-45 24

VIDEO 1

COMPONENT 1

RF

VIDEO 2

COMPONENT 2

HDMI 1

HDMI 2

HDMI 3

PC HD15

USB 1.1

BU

LCD PANEL

TCON

TUNER

IC1301VIDEO

SWITCHVIDEO 3

IC7000AMD

IC4700TRIDENT

SUB VIDEO

ATSC

NTSC

CC VIDEO

MAIN VIDEO

DIGITAL VIDEO

DIGITAL GPX

H/V SYNC

IC5200HDMI

SWITCH & EQ

HDMI 4

LCD PANEL

120HZHFR

TCON

ALL V AND 32/37XBR SERIES

ALL W SERIES

108060HZ

IC3001BE MICRO

IC5000EDID

IC5000EDIDIC5000EDIDIC5000EDIDEDID X4

EDID 1: IC5101EDID 2: IC5191EDID 3: IC5131EDID 4: IC5161

FIGURE 3-1V AND W SERIES VIDEO PROCESS CIRCUITS


CTV-45 25

Z Series Video ProcessingAs illustrated in Figure 3-2, the BU board used in the Z and 40-inch and larger XBR models functions in much the same way as the preceding descriptions of the V and W series with the following differences:

10-bit Video Processing

IC4700 on the BU board outputs 10-bit RGB data instead of the 8-bit level as found on the V and W series. This increases the levels of brightness from 256 to 1,024.

Ethernet Port

Devices that are DNLA (Digital Living Network Alliance) compliant can be used in a network setup to view and listen to content from PC’s, mobile devices, gaming consoles, etc. DNLA provides the standards to allow many devices in the home to receive and send content among the network.

Software upgrades can also be located on the internet and downloaded to the television should it become necessary. More information about the DLNA feature is described in the appendix section of this manual.

USB 2.0 Input

USB storage devices that contain pictures in JPEG format or audio content in MP3 format can be plugged directly into the television for photo viewing or listening to music.

Digital Media Port

Optional devices are available to hook up portable digital video and audio devices to the television. Content can be viewed or listened to along with the ability to control the connected device by using the television screen and remote controller as an interface device.


CTV-45 26

VIDEO 1

COMPONENT 1

RF

VIDEO 2

COMPONENT 2

HDMI 1

HDMI 2

HDMI 3

PC HD15

USB 1.1

BU

TUNER

IC1301VIDEO

SWITCHVIDEO 3

IC7000AMD

IC4700TRIDENT

SUB VIDEO

ATSC

NTSC

CC VIDEO

MAIN VIDEO

DIGITAL VIDEO

DIGITAL GPX

H/V SYNC

IC5200HDMI

SWITCH AND EQ

HDMI 4

108060HZ

LCD PANEL

120HZHFR

TCON

ETHERNET

USB 2.0

PHYSICAL INTERFACE

PHYSICAL INTERFACE

IC3001BE MICRO

DIGITAL MEDIAPORT

IC5000EDID

IC5000EDIDIC5000EDIDIC5000EDIDEDID X4

EDID 1: IC5101EDID 2: IC5191EDID 3: IC5131EDID 4: IC5161

FIGURE 3-2Z SERIES VIDEO PROCESS CIRCUITS


CTV-45 27

TroubleshootingSince virtually all of the video inputs and most of the video processing is located on the BU board, failures causing a loss of video or distortions in the picture need to be isolated to the BU board or the LCD panel. The combining of all video processing circuitry into 2 major components makes the troubleshooting approach to seem rather simplistic and in most cases it will be just so.

As anyone who has experience servicing electronic products knows, things happen in the real world that can cause failures which do not follow the rules of the academic procedures found in this manual. Always research the latest service bulletins and/or troubleshooting tips on the Sony service website before making the service call.

No VideoIf a total loss of video occurs (including OSD graphics) the most likely course of action is to bring a replacement BU board to the service location since the unit is serviced at board-level only. It is unlikely that a loss of voltage from the power supply is the cause since these voltages are monitored and the unit will likely experience a protection shutdown event rather than a no video condition. Although a failure of the backlights to turn on would certainly cause a no video condition, this too would cause the unit to shut down and indicate a failure via the self diagnostics feature. If the replacement BU board does not resolve the issue, the LCD panel is likely defective.

The presence of OSD graphics with a no video condition certainly eliminates the LCD panel as the cause and the BU board will almost certainly fix the problem.

Video DistortionsThis is, by far, the most difficult failure to troubleshoot due to the many sources that can cause it. Noise emanating from the power supply, outside

interferences, video process failures and even mechanical problems in the LCD panel can cause video distortion.

The up-side to display devices is that they are the most valuable tool in determining the source of the problem so long as one knows the basic theory of how they function. The Appendix section of this training manual contains a section on basic troubleshooting of LCD panel televisions. The primary objective when diagnosing no video or distortions in the video is to eliminate the LCD panel as the cause. Replacement of the LCD panel requires special authorization and, in some instances, will not be allowed due to economical reasons.

Troubleshooting FlowchartsDue to the reduced number of circuit boards used in this chassis, troubleshooting video problems must focus on whether the problem lies on the BU board or the LCD panel. In a “no video” symptom the flowchart asks if the backlights are lit. Hypothetically, the backlights must light or the unit will shut down and blink a balancer or inverter error but there have been cases in previous chassis designs where the backlights do not light and the unit did not enter the protect mode. The troubleshooting flowchart in Figure 3-3 will provide some guidance in diagnosing a video problem.


CTV-45 28

Video Failure

Yes

No video or distorted video?

OSD graphics present?

None

Distorted

No

BU Board

All inputs?Yes No

YesNo

HeartbeatLED on BU

board flashing ?

No

Yes

BU Board

Unplug LVDS connector at

TCON while unit is running . This may need to be done more than

once

Any flashes seen on screen?

Yes

BU Board

NoLCD Panel

Backlights turning on ?

Yes

NoBacklight failure

BU Board

Distortion stationary? BU Board

Symentrical?Yes

LCD Panel

Lines single or multi-colored

Multi-colored

Single Color

BU Board

LCD Panel

No

FIGURE 3-3VIDEO FAILURE TROUBLESHOOTING FLOWCHART

CTV-45 29

Chapter 4 – Audio Process Circuits

OverviewAll audio processing and amplification are performed on the BU board. The path of the audio processing differs depending on the source. Figure 4-1 illustrates an overall block diagram of the audio circuits on the BU board.

General Audio ProcessingAll audio processing is selected and performed by IC2002. The IC contains internal switching circuits along with a digital signal processor for equalizer and sound effects control. Analog signals are A/D converted before being processed. Digital audio sources are received via the I2S audio data bus.

Regardless of the audio source type, IC2002 outputs the processed audio as PWM for amplification by IC2005. The selected audio is also output as L/R analog to the rear audio output jacks and the optical output. Audio content from the optical output jack is limited.

Included in Figure 4-1 is a truth table for the optical output. The only time 5.1 channel audio is available is when it is received via ATSC tuner sources. This includes terrestrial 8VSB and QAM from cable systems. If a DVD player is connected via HDMI and the DVD output is set to 5.1, the output from the optical jack will be 2-channel PCM only. All analog sources are output as 48 KHZ 2CH PCM. The only time audio is not output is when digital audio is input via the HDMI connectors from a SACD or DVD-Audio disc.

HDMIThe 4 HDMI inputs are selected by HDMI switch and equalizer IC5200. The serial audio data is received by IC4700 where it is converted to I2S format. The digital audio data is transmitted via this bus to IC7300 and output to IC2002.

USB 2.0MP3 audio files can be input to the USB side jack. The USB device is detected and a list of the available audio files can be viewed in the XMedia graphics menu. The audio can be listened to via the television speakers or and external amplifier hooked up to the L/R analog outputs or optical output jack.

Ethernet (DLNA)Audio or video file playback for the DLNA feature is not supported by any of the 2008 EX1 chassis models. Only JPEG files are supported.

TroubleshootingSince all circuitry involving audio processing and amplification is located on the BU board, troubleshooting audio problems consists of determining whether the failure affects all inputs or it is input specific. Failures affecting all inputs would require changing the BU board whereas input specific problems would require eliminating the input device as the source.

Chapter 4 - Audio Process

CTV-45 30

BU

ATSC/NTSC TUNER

IC7000AMD

FE MICRO

Y/C_COMPOSITE 1

COMPOSITE 2

COMPOSITE 3

COMPONENT 2

COMPONENT 1

HDMI 1

PC

IC2002AUDIO SW

DSP

IC2005CLASS D

AUDIO AMP

HDMI 4

HDMI 4 ANALOG

IC4700TRIDENT

OPTICAL OUT

L/R AUDIO OUT

NTSCAUDIO

ATSCAUDIO

HDMI 2

HDMI 3

SPDIF

IC5200HDMI

SWITCH & EQ

USB2.0

ETHERNET

Z MODELS ONLY

I2S

IC2004LINE OUT

AMP

L

R

DIGITAL MEDIA PORT (Z AND LARGE XBR

MODELS ONLY)

I2S IC7500ADC

PWM

I2SAUDIO SOURCE OPTICAL OUTPUT

DIGITAL TUNER

DVD HDMI 5.1

ALL ANALOG INPUTS

NTSC TUNER

SACD VIA HDMI

DVD AUDIO VIA HDMI

5.1 OR 2CH PCM

2CH PCM

2CH PCM

2CH PCM

NO OUTPUT

NO OUTPUT

OPTICAL OUTPUT TRUTH TABLE

USB2.0

ETHERNET

2CH PCM

N/A

FIGURE 4-1AUDIO PROCESS CIRCUITS

CTV-45 31

Chapter 5 - Power SupplyOverviewSeveral power supplies are used in the EX1 chassis. The type of power supply is determined by LCD panel size and the type of inverter circuit used to power the backlights.

All of the power supply designs contain on-board over-voltage and over-current monitoring to stop the switching supply if a problem is detected. If the main switching supply is stopped, the unit will shut down and the time LED will blink in groups of 2. This feature will be discussed in further detail in Chapter 7 where the protection and self-diagnostics features are explained.

G1D/G2D Power SuppliesIn Figure 5-1, an overall block diagram is shown for the G1D and G2D power supply circuits. These power supplies are used on the smaller V series models. The G1D is used in the KDL32L140 and KDL32XBR6. The G2D is used in the KDL37XBR6 and KDL42V4100 models. They are virtually identical in design with the G2D have a larger current producing capacity for the larger LCD panel backlighting. Both power supplies are used in models to provide power to what is known as “indirect inverters”. These inverters contain all of the necessary circuits for generating the high-voltage AC to power the backlights along with current and lamp detection circuits. These inverters will be discussed in detail in Chapter 6.

The power supply consists of 3 major circuits:

Power Factor Control (PFC)The inductive load of the switching power supply circuits causes the voltage and current to be 90 degrees out-of-phase. The PFC circuit compensates for this and makes the power supply appear as a purely resistive load and to use the AC input power more efficiently. This circuit is only present because of requirements by the Western European countries and Canada so they are included on all power supply designs.

By using a PWM generator, switching transistors and coils, the PFC circuit pumps up the rectified 160VDC to approximately 395VDC. This voltage supplies continuous power to the standby supply. Note that even when the main relay RY6101 is open at turn-off, the thermistor NTC01 is passing AC voltage to the bridge rectifier B01. The PFC circuit is turned off but the coils will pass the 160VDC to the standby power supply. PFC activation is accomplished by the power on command entering at pin 1 of CN602 which is high (3.3V) at turn-on.

Standby Power SupplyThis supply runs continuously whenever AC power is applied. It generates 12VDC for the relay RY6101 and 3.3VDC for the microprocessors on the BU board, IR receiver on the H4 board and function LED’s on the H1 board.

Main Switching SupplyThe main switching supply is activated when the power on high command is received at pin 1 of CN602 from the BU board. This also activates the PFC circuit and the DC voltage feeding the main supply rises to approximately 395V. The main switching supply generates 24V for the inverter board(s), unregulated 13V for the audio circuits, and regulated 12V for the BU board.

Note that the KDL42V4100 has dual inverters and that CN603 is used in this model to provide an additional 24VDC source for a second inverter board.

CTV-45 32

Chapter 5. Power Supply Circuits

STBY 3.3V

STBY 12V

AC IN

AC IN

Q302Q901

STANDBY POWER SUPPLY STBY

12V

PRIMARY POWER SUPPLY

IC601Q601, 602

T600

NTC1

RY6101

GND8

REG 12V11

UNREG_13V4

AU GND6

STBY 3.3V3

CN601

TO INVERTER

BD1

Q303

F14A T

IC305

PFCIC801Q800Q802L800

UNREG_24V1

GND6

CN602

POWER_ON1

TO BU BOARD

Q805

UNREG_24V1

GND6

CN603G2D ONLY(42")

G1D (32")G2D (37")

FIGURE 5-1G1/G2D POWER SUPPLY BLOCK DIAGRAM

CTV-45 33


IP5 Power Supply and InverterNew to the 2008 EX1 chassis models, this combination power supply and inverter is found in 40 and 46-inch V and W series models and is illustrated in Figure 5-2. The basic functions of the PFC, standby and main switching supply are the same as the previously described circuits of the G1D and G2D power supplies with the following exception:

Integrated Lamp InverterThe PFC circuit also supplies approximately 395VDC to an inverter circuit consisting primarily of an oscillator/drive circuit and high-voltage step up transformer and switching transistors.

Approximately 5 seconds after the unit is turned on, a high (3.3V) is received via pin 4 of CN6154 from the BU board. This causes the inverter to output approximately 1KV of 51KHZ AC to drive the fluorescent backlights. The lamp voltage consists of 2 180 degree out-of-phase voltages which are sent to the balancer board. This AC voltage is not continuous. The duration of the AC varies depending on the brightness setting of the backlights. This is controlled by the dimmer line at pin 5 of CN6154. The dimmer control is a negative going PWM signal that varies between approximately 6% at full brightness to 70% at minimum brightness.

Operation of the inverter, along with example waveforms, is covered in more detail in Chapter 6.

G4 Power SupplyThis power supply is used in the 40 and 46-inch Z and XBR6 models and is shown in Figure 5-3. The standby and main switching supplies operate in the same manner as the previously covered power supply circuits.

PFC OutputThese models use a stand-alone inverter located on the D3 board. The inverter requires 395VDC and this is supplied by the PFC circuit via CN6502 to the D3 board.

Warning: When the unit is turned off while still connected to AC power, the rectified 160 volts will pass through the PFC circuit and always be present. This voltage is referenced to hot ground. Use caution when near this circuit and make sure to use an isolation transformer when using grounded test equipment.

G5 Power SupplyFigure 5-4 illustrates the block diagram for the G5 power supply board used in the 52-inch V and W series models (including the 52XBR6). This power supply has a larger current capacity and dual PFC outputs. The 52-inch panels use 2 inverter boards (D4 and D5) requiring the dual PFC lines.

CTV-45 34


IP5

PH6300

PFC

Q6404Q6304Q6303

IC6200T6200

STANDBY POWER SUPPLY

STBY 12V

IC6100Q6100Q6101T6100


HV+ OUT1

HV- OUT3

395VDC

STBY3.33

AC_DET2

CN6502

TO BALANCER

PWR_ON1

UNREG 15V4

UNREG 15V GND6

CN6150

REG 12V11

GND8STBY 12V

FROM BU BOARD

NOT USED

FROM BU BOARD

AC IN

AC IN

R6009

RY6000

D6000

F60016.3A

IC6701Q6706, 6707

T6800Q6602, 6603T6600, 6601

INVERTER

REG 12V1

GND3

CN6151

GND9

GND10

CN6154

INVERTER_ERR3

BACKLIGHT_ON4

5 DIMMER

IP5

FIGURE 5-2IP5 POWER SUPPLY/INVERTER BLOCK DIAGRAM

CTV-45 35


CN6501

PH6300

AC IN

AC IN

PFC

Q6407Q6304Q6303

IC6200T6200


STBY 3.3V

STBY 12V

IC6100Q6100Q6101T6101


R6009

RY6000

PFC OUT1

PFC GND2

395VDC

TO D3 BOARD

D6000

F60006.3A

RLY_VCC(REG 12V)

STBY 12V

REG12_GND8

UNREG_15V4

STBY3.33

AC_OFF_DET2

REG12V13

POWER_ON1

UNREG_GND6

G4

CN6202

TO BU BOARD

395VDC

FIGURE 5-3G4 POWER SUPPLY BLOCK DIAGRAM

CTV-45 36


CN6501

PH6300

AC IN

AC IN

PFC

Q6407Q6304Q6303

IC6200T6200


STBY 3.3V

STBY 12V

IC6100Q6100Q6101T6101


R6009

RY6000

PFC OUT1

PRI GND2

PFC OUT1

PRI GND2

390VDC

CN6500

TO D4 BOARD

TO D5 BOARD

D6000

F60006.3A

RLY_VCC(REG 12V)

STBY 12V

REG12_GND8

UNREG_15V4

STBY3.33

AC_OFF_DET2

REG12V13

POWER_ON1

UNREG_GND6

G5

DIMMER2

BALANCE_ERR7

INV_ERR4

REG12V6

BACKLIGHT3

INV_ERR3

DIMMER5

BALANCE_ERR1

BACKLIGHT4

REG 12V1

GROUND3

CN6100

CN6154

CN6153

CN6150

TO TCON

TO BU BOARD

TO D4 BOARD

TO BU BOARD

FIGURE 5-4G5 POWER SUPPLY BLOCK DIAGRAM

CTV-45 37


TroubleshootingIn order to properly diagnose a potential problem with the power supply it is important to determine if the power supply is completely dead or will not turn on when commanded to do so. There are a couple of important items to be aware of when first examining the unit.

In a properly functioning unit the standby 3.3V line will remain at this voltage for approximately 2 ½ minutes after the AC source is removed. This is part of the AC detect routine and allows the BE Micro to remain running and clear the operational routines to prevent lockup because of a decaying standby voltage.

If the unit was not in the “on” position before AC power was removed and has not had AC power applied for approximately 2 ½ minutes, the BU board will output a power on command to turn on the relay as soon as AC power is returned. The power LED will not light. The distinct click of the AC relay can easily be heard and it will remain engaged for approximately 30 seconds before turning off. This is very important to know when determining if the standby supply, AC relay and BE micro on the BU board is functioning. If has been less than 2 ½ minutes since AC power was disconnected the relay will not perform this routine. If the unit was turned on when the AC power was disconnected, it will power up completely regardless of how long AC power was disconnected.

When the television is working properly the AC relay will not disengage at turn-off until approximately 20 seconds has elapsed.

The following troubleshooting procedures will deal with general approaches to locating the problem. The troubleshooting flowcharts at the end of this chapter are created to specifically address the unit based on what power supply is used,

Completely Dead UnitSince the EX1 chassis models do not use a power standby LED, it becomes necessary to determine if the standby power supply is operating. Unplug the unit from the AC source and wait for 3 minutes. Plug the unit back in and listen for the sound of the relay clicking. If it does, the standby supply is operating. This also confirms that the BE Micro is able to turn on the relay. At this point it is confirmed that the main switching regulator is probably at fault although it is unusual for this to happen without the 12V LVP circuit detecting it and shutting the unit down with a 2 blink diagnostics indication.

Power Supply ShutdownIf the power supply manages to turn on and then turns off, there are a couple of reasons that could cause this. If the main switching regulator does not turn on, the loss of REG12V will be detected and the unit will shut down and the standby LED will blink in sets of 2.

The same event occurs when there is excessive current being drawn on the secondary supply lines from the main switching regulator which has its own over-current detection circuit. This causes the switching oscillator to stop and one of the results is the loss of the REG12V line.

Power Supply Troubleshooting FlowchartThe troubleshooting flowchart in Figure 5-5 will assist in determining the cause of a no power condition.

CTV-45 38


No Power

STBY3.3V CN1411 -3 on

BU board?

Replace Power Supply

Relay click heard?

No


Unplug unit from AC and wait 3 minutes. Re-

apply AC power .

Yes No

Yes POWER_ON 3.3V CN1411 -1

BU Board?

No


Replace BU Board

Yes

FIGURE 5-5NO POWER TROUBLESHOOTING FLOWCHART

CTV-45 39

Chapter 6 - Panel Backlight CircuitsOverviewAll models in the EX1 chassis series use fluorescent tubes to provide the backlighting necessary for the LCD panel. The Z and W series models use conventional cold-cathode fluorescent (CCFL) lights while the Z series utilize Wide Color Gamut lamps (WCGCCFL). The lamps on all panels are arranged horizontally and evenly spaced from top to bottom. The number of lamps ranges from 16 for the 32-inch panels to 24 for the 52-inch.

The primary difference among the various panel sizes and designs is the type of backlighting circuitry and monitoring that is used. The following diagrams and circuit descriptions will be covered separately based on these differences.

32/37-inch BacklightingFigure 6-1 illustrates a block diagram of the circuits involved in generating the backlight voltage for the lamps. The smaller 32 and 37-inch panels use a single inverter board to supply an AC voltage of approximately 1000-volts RMS at 57KHZ.

Power-Up SequenceOnce the power on command is received at CN602-1 on the G board from BE Micro IC3001, the power supply starts and, along with other secondary voltages, outputs 24VDC to CN001 on the inverter board.

Approximately 5 seconds after turn-on, the backlight on command goes high at CN1401-4 on the BU board. The oscillator on the inverter will start and the drive circuits for each pair of lamps will begin generating the necessary lamp voltage.

Inverter CircuitNote that each inverter-drive circuit feeds a pair of lamps. Since each pair of lamps is connected to the opposite end of a transformer they are driven with out-of-phase AC voltage. This is necessary to prevent parasitic capacitance between the lamps to prevent brightness fluctuations.

The AC voltage supplied to the lamps is not a steady voltage. The lamps are provided with a variable duty cycle of AC bursts. This is how the unit is able to vary the brightness of the backlights. The duty cycle of these burst will vary from 30% at minimum brightness up to 95% at maximum. The lamp brightness is controlled by the dimmer line exiting the BU board at CN1401-5. This control line is a negative going PWM signal that will vary its duty cycle from approximately 70% negative at low brightness to approximately 10% at high brightness. This duty cycle change affects the DC voltage at this point and it can be read with a DVM. The DC voltage reads 0.8 volts at low brightness and 3.1 volts at full brightness. Typical waveforms for the inverter output and dimmer PWM signals are shown in Figure 6-2.

The inverter board also contains monitoring circuits (not shown) to detect a failure of one or more of the inverters or if one or more of the lamps fails to light. If either one of these situations occurs, the inverter will send out a high on the INV-ERR line to CN1401-3. This is detected by BE Micro IC3001 on the BU board. IC3001 will shut the unit down and the standby LED will blink in groups of 6.

NOTE: Whenver an inverter error is detected, the unit will make 3 attempts to start the inverter. The AC relay will be heard cycling on and off during these attempts.

CTV-45 40

Chapter 6. Backlight Circuits

FIGURE 6-132/37-INCH PANEL BACKLIGHT DIAGRAM

BU

LCD PANEL

INVERTER DRIVE

INVERTER DRIVE

CN601

PIN 1~524VDC

G1D (32")G2D (37")

CN602-1

GNDINV_ERR

BACKLIGHT_ONDIMMER

CN14012345

CN001

POWER_ON1

IC3001BE

MICRO

CN1411POWER_ON 1

INV_ERR (NORMALLY LOW)BACKLIGHT_ON (3.3V ON)DIMMER (PWM)

POWER_ON3.3V = ON

APPROXIMATELY IKV RMS

INVERTER

CTV-45 41


FIGURE 6-2INVERTER WAVEFORMS

DIMMER MAX BACKLIGHT PWM DIMMER MINIMUM BACKLIGHT PWM

MAX BACKLIGHT AC DUTY CYCLE MINIMUM BACKLIGHT AC DUTY CYCLE

2ms1V/div

2ms1V/div

2ms10V/div

Indirect coupling

2ms10V/div

Indirect coupling

CTV-45 42


42-inch BacklightingThe KDL42V4100 is unique in that this model is the only one that uses this panel design and backlighting scheme. The board layout is shown in Figure 6-3. The G2D power supply used in the 37-inch panel contains an extra connector for an additional 24VDC source and this is used to power the additional inverter board found on this model.

BU

LCD PANEL

INVERTER DRIVE

INVERTER DRIVE

CN601

PIN 1~524VDC

G2D

CN602-1

GNDINV_ERR

BACKLIGHT_ONDIMMER

CN14012345

CN001

POWER_ON1

IC3001BE

MICRO

CN1411POWER_ON 1

INV_ERR (NORMALLY LOW)BACKLIGHT_ON (3.3V ON)DIMMER (PWM)

POWER_ON3.3V = ON

APPROXIKV RMS

INVERTER

INVERTER DRIVE

INVERTER DRIVE

CN001

INVERTER

CN603

CN24

CN23

CN26

CN25

Power-up and protection functions very much the same way as the system used in the 32/37-inch panels with the exception of the additional inverter. Due to the longer length of the backlight tubes, differential AC is applied to both ends of the fluorescent lamps instead of using a common ground reference.

FIGURE 6-342-INCH PANEL BACKLIGHT DIAGRAM

CTV-45 43


40/46 V and W Series BacklightingThese LCD panels have a considerably different backlighting arrangement than those seen in the previous circuit descriptions. High voltage for the lamps is generated on a separate inverter circuit that is part of the power supply board. A balancer circuit has been added in addition to the inverter and will be explained separately. A basic block diagram is shown in Figure 6-4.

InverterOnce the IP5 board receives a power on high at CN6150-1 the power supply begins generating the necessary voltages. The PFC circuit increases the rectified 160VDC to approximately 395VDC to supply power for the inverter switching transistors. The oscillator provides the necessary 41KHZ drive for the inverter switching transistors. The inverter stage outputs approximately 1000VRMS at 2 output lines that are 180 degrees out-of-phase.

Note the inverter detect stage. The detector consists of small-value capacitors and diodes to detect the AC voltage. If either AC line fails to output the inverter detect circuits will output a high to CN6154-3. This will be detected by BE Micro IC3001 on the BU board and the unit will shut down and blink the standby LED in groups of 6. The event will also be registered into the diagnostics menu for viewing when entering that mode. This will be covered in Chapter 7.

The inverter also has over-voltage and over-current detection circuits (not shown). If either circuit detects a malfunction the oscillator will stop and create an inverter detect failure.

CTV-45 44


INVDET

BUIP5

OSC/DRV

CN1411

PFC

IC3001BE

MICRODIMMER5

BACKLIGHT ON4INVERTER_ERR3

GROUND2BALANCER_ERR1

POWER_ON1

CN1401

CN6154

CN6150

LD 6GND 4FB 2

12V 1

LCD PANEL

BALANCEERROR

DET

BALANCER

CN6701

1000VRMS

1 – BALANCER ERROR (NORM LOW)2 – GROUND3 – INVERTER ERROR (NORM LOW)4 – BACKLIGHT (3.3V ON)5 – DIMMER (0.8 ~ 3.1VDC)INVERTER

1 – 12VDC B+2 – FB (FEEDBACK) 7.2VPP4 – GROUND6 – LD (LAMP DET) NORM HIGH (12V)

FIGURE 6-440/46-INCH V AND W SERIES PANEL BACKLIGHT DIAGRAM

CTV-45 45


BalancerThe problem that arises when feeding high voltage to parallel arranged fluorescent lamps is making sure all of the lamps are “struck” or, in other words, ignited to their ionization point. When the inverter is initially turned on it generates a brief period of approximately 2 to 3 times the operating voltage to strike the lamps. If one or more of the lamps does not ignite, the remaining lamps that did will clamp the initial strike voltage and that lamp will not light. The other issue is maintaining even current draw among all of the lamps during normal operation to ensure even backlighting of the panel. A circuit that is designed to balance the current among the lamps is necessary.

The balancer performs several distinct functions and a basic block diagram of the type used in a 40” model is illustrated in Figure 6-5.

Distribution of the high voltage: The 2 out-of-phase high voltage lines are applied to each lamp with one line each feeding every other lamp. The lamps are driven with every other lamp out-of-phase in order to localize the high voltage field around each lamp and keep them from causing brightness fluctuations in adjacent lamps and minimize interference to the LCD panel.

Maintaining Lamp Current Balance: Since the lamps are being driven by a common power source and are arranged in a parallel configuration, variances in lamp tolerances and aging of the lamps requires that the current drawn by the lamps be maintained steady to achieve balanced brightness (hence, the name “balancer board”). Each lamp is supplied with high voltage through the primary winding of a transformer. The secondary windings of each transformer are connected in series to form a closed loop. The circulating current in the secondary loop is what maintains the balance of the current being drawn by the lamps.

As long as all of the lamps are drawing acceptable current, the magnetizing energy between the primary and secondary of each transformer cancels each other out and prevents an inductive flux from being generated. If a lamp’s current draw drops, a differential in current will occur and the secondary will induce the difference into the primary and maintain balance in the current among the lamps. The circuit also helps during the initial “strike” of the lamps at turn-on since any lamp that does not light in unison

with the others will receive a “kick” due to the imbalance on its transformer. In theory, assuming all of the lamps are identical and consuming exactly the same amount of current, the voltage in the secondary winding loop would be near zero. In reality, there will be some voltage in the loop as it performs its job of maintaining balance among the lamps and this is acceptable to a certain point. This is where the secondary loop functions as a protect circuit.

Open Lamp Protection: If one or more of the lamps fails to draw adequate current, the unit must go into protect mode since an out of balance condition can damage the other lamps and also cause damage to the circuit board due to arcing. This generally occurs when a lamp has weakened to the point where it will not turn on when struck. In this situation, there will be little or no current in the primary winding of that lamp and the current differential will cause an induced voltage between the primary and secondary windings. Once the secondary loop induces into the primary winding of the defective lamp, the primary begins to induce back into the secondary. This causes the voltage level to rise in the loop.

4 sampling “taps” are taken along the secondary windings consisting of a resistor divider network and a diode. If an imbalance occurs, the current loop of the secondary windings will now function as a voltage loop. One of the taps will detect a rise and the rectified voltage will exceed the zener diode rating (7 volts). A comparator detects the zener diode firing and sends a high to an inverter. Under normal conditions, the Lamp Detect (LD) line will be high (12VDC) and goes low if one or more open lamps are detected. This is defined as a balancer error and the unit will shut down and blink the standby LED in groups of 13.

Feedback: The final function of the balancer circuit is to provide feedback to the inverter circuit in order indicate overall current draw by the lamps and maintain steady drive voltage. An additional transformer is included in the loop to provide an overall sample. This feedback signal is approximately 7.2VPP. This signal is sent back to the primary inverter (the one with the oscillator) to keep the overall lamp brightness steady.

CTV-45 46


40" PANEL BALANCER

REF

LD (LAMP DETECT)NORM HIGH (12V)

HV IN +

HV IN -

FEEDBACK

TO LAMPS

-+

FIGURE 6-540-INCH BALANCER DIAGRAM

CTV-45 47


40/46 Z Series BacklightingThe LCD panels in the Z series models include the KDL40Z4100, KDL40XBR6, KDL46Z4100 and KDL46XBR6. All functions previously described for the V and W series backlight circuits apply except that the inverter is not integrated with the power supply.

These models use a G4 power supply and a separate D3 board that contains the inverter circuits. The balancer circuit is identical. A block diagram of the backlighting circuits for this series is shown in Figure 6-6.

All 52-inch Series BacklightingAll 52-inch EX1 chassis models utilize the backlighting circuitry illustrated in Figure 6-7. The longer backlights require the use of a floating AC power system to prevent exterior current leakage along the lamps. If a common ground connection is used with a single phased AC at one end of the lamp, brightness would be less in the middle of the lamp than at the edges. This requires the use of a different power supply board and 2 inverters. Since AC is applied to both ends of the lamps, separate balancers are required on the left and right side of the panel.

G5 BoardOperating the same as the G4 board previously mentioned for the 40/46Z models, the G5 power supply provides an additional PFC 395VDC output for the second inverter board.

D4 BoardThis board is similar to the D3 board used in the 40/46Z series models in that it generates dual out-of-phase AC voltage for the lamps. It also contains the master oscillator and drive circuits for the on-board inverter switching transistors. This oscillator and drive circuit is responsible for driving the switching transistors on the D5 board.

D5 BoardThis board drives the opposite side of each lamp with 180 degree out-of-phase AC. Since the D4 board contains the master oscillator and drive circuits, this is how the 2 inverters are able to maintain their out-of-phase condition to drive the lamps.

Note that the D5 board also contains an inverter detect circuit should one or more of the AC output lines fail. Although the intention is to warn the unit and shut it down when the inverter fails, this will not happen if the D4 board is still operational. The inverter detect circuit on the functioning D4 board will keep the inverter-error line low and prevent an inverter failure warning from being detected. The balancer error detect circuits will activate and shut the unit down with a 13-blink error instead. This subject, along with how to isolate it, will be covered in the troubleshooting section in this chapter.

CTV-45 48


BALANCEERROR

DET

BALANCER

INVDET

INVERTER

D3

G4

CN6600

LCD PANEL

OSC/DRV

AC_RLYPFC

CN6600

CN6502

BU

IC3001BE

MICRO

DIMMER5BACKLIGHT ON4INVERTER_ERR3


POWER_ON1

CN1401

CN6702

CN6150CN1411

GND 4

12V 1CN6701

1000VRMS

LD 6

FB 2


CN6701

1 – 395VDC3 – HOT GND

1 – BALANCER ERROR (NORM LOW)2 – GROUND3 – INVERTER ERROR (NORM LOW)4 – BACKLIGHT (3.3V ON)5 – DIMMER (0.8 ~ 3.1VDC)

FIGURE 6-640/46-INCH Z SERIES PANEL BACKLIGHT DIAGRAM

CTV-45 49


UPPER AND LOWER LEFT BALANCERS

INVDET

INVERTER

D4

G5

CN6702

1 – 395VDC3 – HOT GND

OSC/DRV

CN6153

PFC

CN6600

CN6500CN6501

BU

IC3001BE

MICRODIMMER5

BACKLIGHT ON4INVERTER_ERR3


POWER_ON1

CN1401

CN6154

CN6150CN1411

GND 4

12V 1CN6706

FB 2800VRMS

BALANCEERROR

DET

UPPER AND LOWER RIGHT BALANCERS

BALANCEERROR

DET

INVERTERINVDET

D5

LD 6

LCD PANEL

CN6950CN6703

CN61541 – BALANCER_ERR (NORM LOW)2 – GROUND3 – INV_ERR (NORM LOW)4 – BACKLIGHT_ON (3.3V ON)5 – DIMMER (PWM)6 – REG_12V

CN6600

CN6154


REG_12V6

CN5900

FIGURE 6-752-INCH PANEL BACKLIGHT DIAGRAM

CTV-45 50


TroubleshootingFailures that occur in the backlighting circuits that cause the unit to shut down can be caused by one or both of the following reasons:

• Inverter Failures

• Backlight Balancer errors

Inverter FailuresThe following description will involve the single inverter panel. Panels using dual inverters have a slightly different reaction to inverter issues and these will be discussed separately.

If the inverter fails to turn on, or if it turns on and goes into protective stop, the unit will shut down and the standby LED will blink in groups of 6 after the unit has made 3 attempts to start the inverter. Inverter circuits contain the necessary components to detect the presence of the high voltage AC generated by the switching transistors and transformer. If one or both of the differential phased AC lines fails to output, the inverter detect circuit will cause the normally low inverter error line to go high. This event is detected by IC3001 on the BU board. The event will also be recorded into NVM for display when the diagnostics page is called up and this feature will be covered in Chapter 7.

Inverter Does Not StartIf the inverter fails to start, this is easy to detect. The backlights should turn on approximately 5 seconds after the unit is powered up. Except for extremely high ambient lighting conditions, you should be able to detect the lighting of the backlights. Many of the newer panels have multiple holes in the rear of the panel where the backlights can be viewed even if the rear cover is on. If the backlights never turn on and the unit shuts down with a backlight failure indication it is safe to assume one of the following circuits is the cause.

Inverter: Check for the presence of 395VDC at CN6600 on the DF1 board. This voltage line is referenced to hot ground so you will have to read across pins 1 and 3 of the connector. There is a fusible resistor

(0.1 ohm, 1/2 watt) in line with this voltage on the power supply and they occasionally open. Check for the backlight on command at CN1401-4 on the BU board. It should go high to around 3.3VDC about 5 seconds after the unit is turned on. It is extremely rare for this to be the cause but if it does not go high, There is a connection problem at the power on line or the BU board is defective. If all of the above checks out OK, replace the inverter board.

Power Supply: If the power supply is not outputting the 395 volts, replace the board if the unit is under warranty. Models using the IP5 combination power supply and inverter would simply require replacing that board under this and the previous condition.

BU Board: If the BE Micro on the FB board fails to send a 3.3V backlight on command the unit will shut down as if the inverter had failed. Be certain to record the serial number of the unit so the correct version of FB board can be ordered. The version of FB board is determined by which LCD panel was installed during the manufacturing process.

Inverter Starts and Turns OffThis is easily identified by the brief presence of backlighting before the unit shuts down. The EX1 chassis will attempt to run the inverter 3 times before shutting down. The inverter board contains over-voltage and over-current detection circuits. These circuits usually activate because of a problem on the inverter board. On units that have balancer circuits, one item that can cause an over-voltage shutdown of the inverter is the feedback from the balancer board. If this feedback line fails, the inverter regulation line will apply full power in an attempt to get a feedback reading. This excessive voltage will activate the OVP circuit located on the nverter board. You will need an oscilloscope to check the feedback line at pin 4 of CN6702 on the DF1 board. It is normally around 7.2VPP a will have the same wave shape as the AC power driving the lamps. If it is very low or not present, the balancer is the most likely cause of the problem.

CTV-45 51


Dual Inverter CircuitsThe use of dual inverters can produce symptoms that will not be seen on single inverter designs. Note that the DF4 board contains the oscillator to drive the inverter on both the DF4 and DF5 boards. The common oscillator and drive circuits are needed to keep the lamp voltages out-of-phase at the opposite ends of the lamps. In this design a unique situation occurs if the inverter fails on the DF5 board.

Note that both inverters have a detect circuit. Both detect lines actually tie together on the DF4 board. The problem with this design is that if only the inverter on the DF5 board fails, the inverter on the DF4 board will still be functioning because that is where the oscillator/drive circuits are located. This will cause the functioning inverter on the DF4 board to keep the inverter error detect line from activating since the common point of both inverter detect lines are not or-gated to isolate them from one another. The unit will never go into inverter protect shutdown. The balancer error detect circuits will activate and the unit will shut down with 13 blinks instead of 6.

Since the DF4 board is operating, the backlights will light momentarily but if one observes the screen closely, you should notice that the right side is backlit with a little more intensity than the left side. It is subtle, but you should be able to detect it. The same symptom could appear if the inverter were to fail on the DF4 board with the oscillator/drive circuits still functional. This would keep the DF5 board active and the symptoms and shutdown events would be the same except the left side of the screen would have a little brighter backlighting than the right before the unit shuts down.

Balancer ErrorsWhen a balancer error occurs, we at least have the ability to observe the lighting of the lamps before the unit shuts down. The unit must a have a correctly functioning inverter to start the lamps and allow the balancer detect circuit to function. In some cases, the lamps may light long enough to see active video or snow for a couple of seconds. Observing the backlighting of the panel at this time is a great tool in determining what is causing the shutdown.

NOTE: Unlike an inverter error where the unit will make 3 attempts to start the inverter, a blanacer error will cause the unit to cycle 2 times before the protect shutdown occurs.

Remember, the purpose of the balancer detect circuit is to monitor a lamp that will not startup. Unless a particular model has a history of a related component causing balancer error shutdowns to occur, it will usually be a defective lamp and that will require replacement of the entire LCD panel. A lamp that is not lighting is difficult to spot due to the efficiency of the diffuser panel to spread the light.

In models that use inverter boards on both sides, observe the screen for uneven lighting from one side to another. This indicates a faulty inverter board and the side that is darkest is where the failed inverter resides.

CTV-45 52


Balancer Board Removal

A new High voltage connector is used to secure the wires from the inverter to the balancer board(s). It contains an integrated locking device that must be released before the connector can be pulled loose. This procedure is illustrated in Figure 6-8. Once the lock is released, grasp the connector as shown and pull it straight out of the socket. Do not rock the connector to attempt to loosen it or you may damage the connector and/or circuit board.As noted in Figure 6-9, once the screws securing the plastic or metal cover on the balancer board are removed there is usually no more screws securing the balancer board. On some panels there may be an additional screw securing the board once the cover is removed.Do not remove the screws securing the long black plastic strip near the edge of the panel. This contains the sockets for the tabs protruding from the balancer board. The other side of these sockets secures a pin on the end of each fluorescent lamp. If this socket strip is loosened, damage to one or more of the lamps is likely.The balancer board is removed by pulling it sideways and out of the sockets. This may require some effort and “rocking” of the board at the top and bottom ends.

Troubleshooting FlowchartsDue to the various LCD panel designs used in the EX1 chassis it becomes necessary to create troubleshooting flowcharts that are specific to the type of inverter system used. Most balancer errors will end up being caused by a defective lamp in the panel but there is a possibility of an inverter related failure and this is especially true for the 52-inch panels using dual inverters.

Failures within the inverter circuit(s) will require the use of a DVM to assist in isolating the cause. The Flowcharts contained within Figures 6-10 through 6-13 are specific to panel size and design and should prove to be a useful tool when troubleshooting the unit on-site or in the shop.

SLIDE LOCKING TAB IN DIRECTION

OF ARROW TO RELEASE

SQUEEZE BOTH SIDES OF

CONNECTOR AND PULL STRAIGHT OUT

FIGURE 6-8HIGH VOLTAGE LOCKING CONNECTOR

CTV-45 53


BALANCER REMOVAL ISSUE

COVER REMOVAL SCREWS

PULL BALANCER BOARD IN

DIRECTION OF ARROW TO

REMOVE

VIEW OF OTHER SIDE OF BALANCER SOCKETS SECURING

BACKLIGHT LAMP

DO NOT REMOVE THE SCREWS UNDERNEATH THE COVER. THESE SECURE THE

LAMP SOCKETS TO THE PANEL. IF THEY ARE

REMOVED, DAMAGE TO THE BACKLIGHT LAMPS WILL

OCCUR IF THE BALANCER BOARD IS MOVED.

FIGURE 6-9BALANCER BOARD REMOVAL CAUTION

CTV-45 54


32/37" V SERIES PANEL

BACKLIGHT ERROR 6X

Yes

No

CN1401-3ON BU BOARD

GOES HIGH (3.3v)?

YesBU Board

LCD Panel

No32" Panel?

Backlights LightAt turn-on?

No

Yes

24VDC atCN601 -1 on G1D

Board?

No

G1D Board

3.3VDC at CN1401 -4 on BU

Board?

No

BU Board

Yes YesInverter Board

24VDC atCN601-1 on G2D

Board?

No

G1D Board

3.3VDC at CN1401 -4 on BU

Board?

No

BU Board

Yes YesInverter Board

FIGURE 6-1032/37” BACKLIGHT TROUBLESHOOTING FLOWCHART

CTV-45 55


40/46" V AND WSERIES PANEL ERROR

BACKLIGHT 6XBALANCER 13X

6X OR 13X?6X


Yes

No

Backlightslight at

turn-on?

No

Yes CN6701 -1 on IP5 board goes low ?

IP5 Board

BU Board

IP5 Board

LCD Panel

13X

No

Yes

3.3VDCmomentarily at

CN6154 -3IP5

Board?

BU Board

7.2VPPFeedback

CN6701-4 on IP5 Board?

No

Balancer

YesIP5 Board

Yes

No

IP5 Board


CN6154 -4IP5

Board?

Yes

No

FIGURE 6-1140/46 V SERIES BACKLIGHT TROUBLESHOOTING FLOWCHART

CTV-45 56


40/46" ZSERIES PANEL ERROR

BACKLIGHT 6XBALANCER 13X

6X OR 13X?6X


Yes

No

Backlightslight at

turn-on?

No

Yes CN6701 -6 on D3 board goes low ?

D3 Board

G4 Board

D3 Board

LCD Panel

13X

No

Yes


CN6154 -3G4 Board?

BU Board

7.2VPPFeedback

CN6701 -2 on D3 Board?

No

Balancer

YesD3 Board

Yes

No

395VDC across CN6502 on G4

Board?

Yes

No


CN6154 -4G4 Board?

No

BU Board

D3 Board

FIGURE 6-1140/49” Z SERIES BACKLIGHT TROUBLESHOOTING FLOWCHART

CTV-45 57


ALL 52-INCHPANEL ERRORBACKLIGHT 6XBALANCER 13X

6X OR 13X?6X


Yes

No

Backlightslight at

turn-on?

No

Yes CN6706 -6 on D3 board goes low ?

D4 or D5 Board

G5 Board

G5 Board

LCD Panel

13X

No

Yes


CN6154 -3G4 Board?

BU Board

7.2VPPFeedback

CN6706 -2 on D3 Board?

No

Balancer

YesD4 Board

Yes

No

395VDC across CN6500 on G5

Board?

Yes

No


CN6154 -4G5 Board?

No

BU Board

D4 BoardYes

FIGURE 6-12ALL 52” PANEL BACKLIGHT TROUBLESHOOTING FLOWCHART

CTV-45 58

Chapter 7 – Protect Circuits

OverviewKey areas of the television are monitored for protection and, in all cases, will shut the unit down. Once a fault has been detected and the unit has shut down, the BE Micro IC3001 on the BU board will blink the standby LED in repetitive sequences to indicate which fault was detected. The fault will also be recorded into NVM so that the number of times the event occurred can be displayed in the self-diagnostics mode. Figure 7-1 illustrates a simplified block diagram of the various circuits monitored for protection.

Voltage ProtectionLow-voltage protection is monitored at 3 locations and over-voltage protection at 2 places. The unit will shut down if a failure occurs at any of these monitoring points.

DC Detect (2X)

The regulated 12V line from the power supply enters the BU board at pin 1 of CN1411. This line is monitored directly by BE Micro IC3001 as DC_DET. If the REG12V line fails, the unit will shut down and the standby LED will blink in groups of 2.

DC Alert (3X)

This line monitors 3 potential events:

• Over-voltage of the REG5V from IC7132.

• Low voltage of the REG5V from IC7132

• Low voltage of the REG 3.3V

Backlight ProtectionThe inverter circuits are monitored to protect the lamps and the backlight circuits themselves. Monitoring of current drawn by the lamps is also important to protect the inverter and balancer boards.

Inverter Error (6X)

Entering the BU board at pin 3 of CN1401, the inverter error line is normally low. This line goes high whenever the inverter loses one or both of the AC lamp drive outputs. This may occur because of a failure of the inverter or when the inverter is stopped because the OCP or OVP circuits on the inverter board have detected a problem.

If IC3001 detects a high on the inverter error line the unit will make 3 attempts to get the inverter to start running. In almost all cases, the backlights will never light. The exception to this is if the inverter is starting but it’s over or under-voltage circuits are stopping it. During this cycle time the clicking of the main relay will be heard as the unit turns on and off. If the unit was last set to an input with active audio you may hear this for a moment.

Chapter 7 - Protect Circuits

CTV-45 59

Balancer Error (13X)

This protect feature is not utilized in the models using the 32 and 37-inch panels although it appears in the diagnostics screen. Only models that use balancer boards have this feature.

If one or more of the backlight lamps fails to light, the balancer loop will cause the BAL_ERR line at pin 1 of CN1410 to go low from its normally high state (11.5VDC). In virtually all cases you will see the backlights turn on before the unit shuts down. Once a balancer error is detected the unit turns off and blinks the standby LED in groups of 13. Unlike the inverter error detection, the unit will not make another attempt once it shuts down.

This event is most likely caused by a defective lamp. In the models that use 52-inch panels it is possible that one of the 2 inverter boards has failed and can be detected by one side of the screen appearing slightly darker during the brief period before shutdown.

Other ProtectionPower supply, Inverter and balancer errors are the most likely to be remedied outside of the BU board. The remaining protection circuits involve devices mounted on the BU board.

Temperature (7X)

IC3502 located on the BU board is a digital thermometer that sends data directly to IC3001 regarding temperature within the television cabinet. If the specified temperature is exceeded, the unit will shut down with a 7-blink error.

If the unit shuts down immediately after turn-on, suspect a defective IC3001 or an interruption of data on the I2C bus. Shutdown after extended periods of operation may be caused by excessive ambient temperatures or insufficient ventilation.

Speaker Protect (8X)

Any DC detected on the speaker lines will cause this event. It is usually caused by a failed audio amplifier and since all audio components are located on the BU board, this is the component to replace to resolve the issue.

Trident (11X)

If a data reading error occurs between BE Micro IC3001 and Trident video processor IC4700, the data read will be attempted 2 more times and if still unsuccessful, the unit will shut down and blink the standby LED in groups of 11. Replacement of the BU board is recommended.

TCON or HFR (12X 14X)

A communication error has occured from the TCON board. If the LVDS cable is not defective or loose both conditions require the replacement of the LCD panel.

# BLINKS PROBLEM DETECTED POSSIBLE SOLUTION2 LOSS OF REG 12V G BOARD3 5V OR 3.3V OVP OR LVP BU BOARD5 LOSS OF PANEL 12V NOT USED IN CHASSIS6 INVERTER NOT WORKING INVERTER OR G BOARD7 EXCESSIVE TEMPERATURE IF OCCURS IMMEDIATELY REPLACE

BU BOARD8 DC DETECTED ON SPEAKER BU BOARD11 TRIDENT IC PROBLEM BU BOARD12 TCON ERROR LCD PANEL13 BALANCE ERROR (NOT USED IN

32 /37XBR6 MODELS)LCD PANEL

14 HIGH FRAME RATE ERROR LCD PANEL

SELF DIAGNOSTICS TABLE


CTV-45 60

FIGURE 7-1PROTECT CIRCUIT BLOCK DIAGRAM

IC3502TEMP

SENSE

DC_DET (MAIN _POWER)

REG3.3V

DC_ALERT

IC2005AUDIO AMP

INV_ERR 6X

FROM INVERTER

REG 12V 11CN1411

3INV_ERR

CN1401

1BAL_ERR

FROM POWER SUPPLY

IC71325V REG

D7101

Q3415

Q7101

IC3001BE MICRO

2X

3X

BALANCER ERROR* 13X

*NOT USED IN 32/36XBR6 MODELS

8X

7X

IC4700TRIDENT

11X

BU

12X or 14XHFR OR TCON ERROR FROM

LCD PANEL


CTV-45 61

Diagnostics HistoryWhenever a problem is detected by the self-diagnostics feature that causes the unit to shut down, the event is recorded and stored in NVM. This is particularly helpful when dealing with intermittent failures but not so helpful if the unit is always shutting down.

The diagnostics history pages are retrieved by pressing the “DISPLAY”, “5”, “VOL –“ and “POWER“ buttons in sequence on the remote commander when the unit is off. The diagnostics history page will appear as shown in Figure 7-2

There are 2 pages containing failure history. Press the “1” key on the remote to view the second page. Pressing the “4” key returns to the first page.

Note that a running count is kept anytime one of the detection circuits is activated. This running count will continue until it is reset. This is performed by pressing the “8” key on the remote followed by the “0” key. This should always be done in order to clear the history and provide a clean table for future use.

The diagnostics page also contains 4 sets of 5-digit numbers. The first set, beginning at the left, indicates the number of hours, in decimal format, that the set has been operating. The next set is the boot count. This is the number of times the unit has been turned on. The third set is the number of hours the panel has been operating. This number can be reset to zeros by pressing the “7” key followed by the “0” key. Only the panel hours will be reset. The last group is not used in the EX1 chassis.

Troubleshooting FlowchartsThe troubleshooting flowchart found in Figure 7-3 will assist in determining what component is the likely cause of the protect shutdown. Due to the large variances in panel backlight circuitry, shutdowns resulting in 6 or 13 blinks will refer you to another set of flowcharts found in Chapter 6. These flowcharts will steer you in the right direction based on the model of the unit you are servicing.

Troubleshooting Test PointsFigures 7-4 through 7-9 contain illustrations pointing to the important and easily accessed test points for checking voltages and logic levels of protect lines. They are grouped according to panel size and backlight circuitry design.

DIAGNOSTICS HISTORY (PAGE 1)

DIAGNOSTICS HISTORY (PAGE 2)

EVENT COUNT

# BLINKS

OPERATING HOURS

BOOT COUNT

PANEL HOURS NOT USED

FIGURE 7-2SELF-DIAGNOSTICS PAGES


CTV-45 62

FIGURE 7-3PROTECT TROUBLESHOOTING FLOWCHART

Red Standby LED Flashing

No

No

Yes

Yes

2XMAIN POWER

3XDC ALERT

Yes

5XTCON

No

POWER SUPPLY(SEE POWER SUPPLY

TYPE IN APPROPRIATE TRIAGE SHEET)

No

Go To Inverter Troubleshooting

Flowchart

7XTemperature

Yes

Immediately? Check for possible ventilation problem

BU Board

Yes

No

8XSpeaker Protect

Yes

No

6XBACKLIGHT

Yes

C

13XBalancer

Yes Go To Inverter Troubleshooting

Flowchart

BU Board

11XTRIDENT BU Board

Yes

No

No

12X or 14X? LCD PANELYes

No

No

BU Board

NOT USED


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CN3201TO H1, H3 ANDH4 BOARDS

CN1411TO G1D BOARD

CN1401 TO INVERTER1 NOT USED2 GROUND3 INV_ERR (NORM LOW)4 BACKLIGHT ON (3.2V)5 DIMMER (PWM)

CN6011~5 24VDC6~8 GND

CN6021 PWR_ON2 AC_OFF_DET3 STBY_3.34,5 UNREG 13V6~10 GROUND11,12 REG_12V

CN2001TO SPEAKERS

FIGURE 7-432-INCH TEST POINTS


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CN6011 ~ 5 UNREG 24V6 ~ 10 GROUND

CN6021 POWER ON (3.3V ON)2 AC_OFF_DET (NORM HIGH)3 STBY 3.3V4, 5 UNREG 13V6 ~ 10 GROUND11 ~ 13 REG12V

CN14011 NOT USED2 GROUND3 INV_ERR (NORM LOW)4 BACKLIGHT ON (3.2V)5 DIMMER (PWM)

CN1411TO G2D BOARD

CN2001TO SPEAKERS

CN3201TO H1, H3 AND H4 BOARDS



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CN100

CN24

CN1

CN23


CN6021 POWER ON (3.3V ON)2 AC_OFF_DET (NORM HIGH)3 STBY 3.3V4, 5 UNREG 13V6 ~ 10 GROUND11 ~ 13 REG12V

CN14011 NOT USED2 GROUND3 INV_ERR (NORM LOW)4 BACKLIGHT ON (3.2V)5 DIMMER (PWM)

CN1411TO G2D BOARD

CN2001TO SPEAKERS




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CN61541 – BALANCER_ERR (NORM LOW)2 – GROUND3 – INV_ERR (NORM LOW)4 – BACKLIGHT_ON (HIGH ON)5 – DIMMER (PWM)

CN61501 – PWR_ON2 – AC_OFF_DET3 – STBY_3.3V4,5 – UNREG_13V6~10 – GROUND11,12 – REG_12V

CN67011 – REG_12V2,3 – FEEDBACK4,5 – GROUND4,5 – UNREG_13V6,7 – LD (BALANCER_ERR

NORM 11.7VDC)

CN2001TO SPEAKERS

CN1411TO IP5 BOARD


CN104TO BU BOARD

CN101LAMP HIGH VOLTAGE!

CN102LAMP HIGH VOLTAGE!

CN1401TO IP5 BOARD

FIGURE 7-740/46-INCH V AND W TEST POINTS


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CN6700

CN6600

CN6706 TO BALANCER1 REG 12V2,3 FEEDBACK 4,5 GROUND6,7 LD (INV_ERR NORM LOW)

CN6702 FROM BU BOARD1 GROUND2 DIMMER (PWM)3 BACKLIGHT_ON (3.3V ON)4 INV_ERR (NORM LOW)5 REG 12V6 BALANCER_ERR (NORM LOW)

CN62021 POWER_ON2 AC_OFF_DET (NORM 3.3V)3 STBY 3.3V4 NC5 UNREG 13V6~10 GROUND11~13 REG 12V

CN1411 TO G4 BOARD

CN2001TO

SPEAKERS

CN3201H1, H3, H4 AND LOGO

BOARDS

CN1401TO D3

BOARD

CN61031 – PFC 395V2 – PFC GROUND

FIGURE 7-840/46-INCH Z SERIES TEST POINTS


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CN53

CN58FROM G4 BOARD

CN56TO LEFT

BALANCER

CN6700

CN6600

CN6703TO D5 BOARD

CN6702FROM G5 BOARD

CN6154 TO BU BOARD1 – BALANCER ERROR (NORM LOW)2 – GROUND3 – INVERTER ERROR (NORM 3.1V HIGH)4 – BACKLIGHT (3.3V ON)5 – DIMMER (0.8 ~ 3.1VDC)

CN65

CN62CN2001TO SPEAKERS

CN1411TO G5 BOARD


CN1401TO G5 BOARD

CN6153 TO D4 BOARD1 – GROUND2 – DIMMER (PWM)3 – BACKLIGHT_ON (HIGH ON)4 – INV_ERR (NORM LOW)6 – REG_12V7 – BALANCER_ERR (NORM LOW)

CN61501 PWR_ON (3.3V ON)2 AC_OFF_DET (NORM HIGH)3 STBY_3.3V4, 5 UNREG_13V6~10 GROUND11,12 REG_12V

CN6706 TO BALANCER1 – REG_12V2, 3 – FEEDBACK4, 5 – GROUND6, 7 – LD (BALANCER_ERR NORMALLY 11.7VDC)

CN65011 – PFC 395V2 – HOT GROUND

CN6500 CN6950 FROM D4 BOARD3 – INV_DRVL5 – INV_DRVH6 – GROUND8 – V-FB110 – REG_12V

CN6150 TO TCON1, 2 REG_12V3, 4 GROUND

FIGURE 7-952-INCH MODELS TEST POINTS

CTV-45 69

Chapter 8 – Appendix

Software UpdatesSony televisions have become much more reliant on software and firmware over the last couple of years. Digital processing such as decoding the MPEG2 video and Digital Dolby® signals along with scaling of the video signals to the display resolution requires program routines to perform these functions. Add control and protection of the television along with fancy GUI graphics and interfacing with other devices and you can see that these software and firmware files are becoming more complicated.

The files containing operating commands within a television’s CPU or micro-controller are technically known as “firmware” since the information is stored within the controlling devices and may also reside in external NVM or flash memory. Some of the information could be classified as “software” since it can be changed to customize the unit. The word “software” appears on the television screen whenever one wants to check the current version in the unit and also appears whenever an update is being installed. For this reason, the word “software” will be used in this article when referring to any updates.

Why Update?In some cases, updates are necessary to resolve a “glitch” that may have appeared in the operating routine of the television. As mentioned in the beginning of this article, software programs have become quite complex and use of the product in the field can sometimes expose a minor error in the routine of these programs.

It should be noted that most software updates are not provided to increase the picture quality of the television. Proper handling of the video processing tends to be rather accurate at the time the units begin production. A majority of software updates are used to compensate for problems that are not necessarily the television’s fault.

An example would be an issue that arose in one state where an over-the-air television station was failing to transmit a proper piece of information in the overhead data packet in its digital channel. When the customer performed the initial setup routine on their television (which includes the “auto program” to add available channels) the channel search would stop at this station and fail to continue scanning the OTA bands. The television would display most of the analog NTSC stations detected but no digital channels. A software update was provided to the customer to ignore this glitch in the station’s data packet and continue the channel search. This incident affected an isolated region of the country that does not require an update be made available for all models sold.

The software updates tend to be cumulative, in other words, the previously mentioned incident with the television station could arise somewhere else in the country and may be included in future update packages to keep all televisions from running across this problem.

Checking the Version of SoftwareIn certain cases it may be necessary to check which versions of software are currently installed in the unit. The best way is to enter the service mode by pressing “DISPLAY”, “5”, “VOL+” and “POWER”, in sequence, on the remote controller while the unit is off. The installed version of the FE and BE Micros are listed on the first page.

Another method is to enter the customer setup graphics and locate the “Product Support” icon at the upper left of the group. When the “Software Update” icon is selected the current installed software is displayed in a coded format that can be mathematically converted to the software version. This method is used by the initial tiers of customer support to determine if the unit should receive an update.

Chapter 8 - Appendix

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FIGURE 8-1SOFTWARE VERSION CHECK VIA XMB MENU

FIGURE 8-2SOFTWARE VERSION CHECK VIA SERVICE MODE


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Performing the UpdateSony televisions manufactured in the last 3 years contain a USB port located on the rear of the unit. On 2007 and 2008 models this port is labeled “DMEX/SERVICE”. DMEX (Digital Medial Extender) is used for optional devices such as the Bravia Internet Video Link to allow the television to access selected internet websites. It also serves as the input port for software updates via a USB storage device. Units manufactured prior to 2007 have a hidden USB port that is accessed by removing a small cover on the rear of the unit.

In situations such as the television station issue described above, Sony can send a USB device pre-loaded with the necessary software to update the unit to resolve the issue. This is one way for customers to receive an update for their television. The update will be supplied with full instructions on how to install the file(s). Another way to receive updates is for the customer to download the required file(s), place them on a USB device, and then perform the update.

The 2008 model lineup includes a feature that can allow the television to automatically receive updates should they become necessary. One feature uses a selected local channel to provide the data for the update via the onboard tuner. When the television is turned off, the tuner continues to operate in standby and extracts update information in small groups. Once the entire file has been extracted, the update can be installed by the customer via the user menu.

Another option that is found on some of the upper-end models is the use of an Ethernet port located on the rear of the unit. This allows the television to be connected to a home network. This feature only works with networks and devices that are set up to be DLNA (Digital Living Network Alliance) compliant. Information on this system can be found at www.dlna.org. The customer can download the update and retrieve it directly from the computer on the home network. Be aware that although these features are present on selected models, their practical use has not been finalized as of this writing and will be covered if and when they become fully functional for this year’s applicable models. FIGURE 8-3

DMEX/SERVICE USB PORT

NOTE: Most updates are performed by the customer. In certain cases where access to the service mode is required, the technician will perform the update and then access the service mode to change or adjust any additional items. Always verify whether an update is required by a technical person. Failure to do so will result in a rejected warranty claim.

http://www.dlna.org


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Downloading an UpdateUpdates can be downloaded in several ways. The customer may be given a specific URL to do this or, if the update is required for all units, may be located on the Sony customer support website. If the update requires the expertise of a service technician it may be located in the ASC service website (currently ESI). The location for downloading an update will also contain documentation with the proper instructions for the install. Read this information very carefully. Some televisions have the update file located within a folder and others do not. If the television requires a folder, this is the first item the unit will look for on the USB device. The file will be in zip format with the folder and update file included. If the update has a single file and a folder is not required it can be sent without having to compress it to a zip format.

Formatting the USB Device

It is important that the USB device not contain any additional files or folders before placing the update information on it. The best way to do this is to right click on the device in Windows Explorer and select “format” from the dropdown menu. Make sure the file format is set for FAT32. If the USB device is more than 2GB Windows Explorer will force FAT32. Formatting the device will remove any hidden files or partitions that may reside on the device.

Installing the File(s) to the USB Device

If the update information is in zipped format it is best to download the file to your computer’s hard disc. When the file is opened, unzip its contents directly to the USB device. This assures that the folder (if used) is properly placed on the device with the update files inside the folder.


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Updating the TelevisionThe new 2008 EX1 chassis will be used as an example in this writing. Procedures vary with chassis designs. Some require inserting the device with the television off and then booting the update by turning it on. Most of the units will read the device when it is inserted while they are powered on. Updates for the EX1 chassis are performed by inserting the USB device while the unit is turned on. The update may require up to 10 minutes. The total update time in this example took 7 minutes and 20 seconds. The following sequence of events will occur and is shown in the succeeding illustrations:USB Detection and File Loading

Once the USB device is inserted it will be detected. A blue splash screen will appear with the graphics at the upper left of the screen will displaying a toolbox and the words “Software Update”. The file(s) are then copied from the USB device.

Notification of Update

This information will appear on 2 pages. The first will indicate that a mandatory update will occur and the current software version is shown along with the version that will be installed. The second page explains the procedure and the approximate time it will take along with a warning not to interrupt or turn off power to the television during the procedure.

FE Micro Update

If active video was present before the USB device was installed it will return for several seconds. Another splash screen will appear with a moving progress bar. The FE Micro is contained within the AMD decoder IC. The BE Micro and video processor are still functioning and this is why graphics can be generated. This process may continue for several minutes. Once complete, the screen will return to active video (if present) for several seconds before the BE Micro begins its update.

BE Micro Update

Since the BE Micro controls the video processor, the screen will go blank with no video or graphics displayed. The Standby LED on the lower right corner will light a steady red while the PIC OFF/TIMER LED lights amber colored with a slow blink rate. This is the only indication that the update is still in progress.

Update Completion

Once the unit has completed the BE Micro update, active video and audio will once again appear followed by an indication that updating is being finalized. The last screen will indicate a successful install of the update and prompt the removal of the USB device. Press the center joystick button on the remote controller to clear the screen.


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SOFTWARE FILES UPLOADING INFORMATION PAGE

UPDATE PROCEDURE INSTRUCTIONS FE MICRO (AMD) UPDATING

FIGURE 8-3SOFTWARE UPDATE SEQUENCE


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SOFTWARE INSTALL COMPLETE

BE MICRO UPDATING

TIMER LED WILL BE BLINKING

STANDBY LED STEADY RED

FINAL INSTALLATION

FIGURE 8-3SOFTWARE UPDATE SEQUENCE (CONT)


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LCD Panel TroubleshootingWhen a customer calls and is complaining of “poor picture quality”, “colored lines”, or no picture at all, it is very important that the technician rule out the LCD panel assembly as the cause. Technicians should be using the triage system found on the ASC Portal site and in the back of the training manuals to assist on which parts should be brought to the location to service the unit. LCD panels are not suggested to be brought to the service location based on the customer’s description of the problem. They are expensive to ship and prone to damage. The technician must diagnose the unit and obtain special authorization before the panel can be replaced. In certain cases it may be determined that it is not economically feasible to replace an LCD panel for a particular model and that replacement of the unit would be the best option.

The purpose of this article is to assist the technician in determining if the LCD panel is defective as efficiently as possible. In many cases, failures of the physical aspects of the panel (panel glass damage, tab bonding issues) are easily recognized. Failures of the TCON board (which is considered part of the panel) can sometimes lead the technician to erroneously change a video process board and have wasted time only to find out that panel is the cause of the failure.

LCD Panel BasicsLCD panels have steadily evolved over the last several years. New designs of the physical structure of the LCD crystals have greatly improved the contrast ratio and viewing angle. Quicker response times and increased refresh rates have helped to reduce the motion “smear” associated with LCD displays. Backlighting design has also aided in producing a picture with color temperatures to make the images as true as possible. With all these design improvements, one aspect of the LCD panel remains relatively the same: Processing of the video signal.

Figure 8-4 illustrates a typical LCD panel and the associated video processing circuits as found in the WAX3 chassis. The various formats and resolutions of video signals are processed on the BU1 board. All video signals exit the video processor in the native resolution of the LCD panel. In this design, the resolution is for a 1280 by 768 at 60HZ refresh rate panel. 48 horizontal lines are discarded to match up to the 720p resolution of the ATSC specifications so the video will exit as 720p.

The LCD panel used in this model processes 8-bit RGB video data. Before the video information can be sent to the TCON board it must be converted to a format that allows for practical and noise-free transmission. The large number of parallel lines to transmit the 8-bit RGB data would need to be sent on differential lines for noise reduction. This would require 48 lines just for the video. The TCON circuit also requires B+, ground connections, a communications bus, sync, and a clocking line transmitted differentially so we can see that up to 100 lines would be required. The practical way to transmit this information is to convert the parallel video data to a serial stream and this is accomplished by the Low-Voltage Differential Signaling (LVDS) transmitter.

The LVDS transmitter contains a circuit to serialize the parallel data. The parallel video information along with sync and clocking data are transmitted via twisted line pairs. Depending on the logic level, current is sent along one or the other of the twisted pair of wires. The receiving end of the wires is loaded with a resistor (usually around 100 to 120 ohms). The receiver detects the polarity of the voltage drop across the resistor to determine the logic level. The current level swings in the wire are about 3ma with a voltage differential of around 350mv. This allows for transmission of the video signal with minimal EMI.

The LVDS receiver on the TCON board converts the serialized data back to parallel. This data is processed by the timing control IC to allocate the RGB data into serial streams for processing by the LCD panel. The LCD panel contains shift registers and drivers for all of the rows and columns of pixels on the panel. The drivers are mounted on flexible circuit boards and bonded to the top and side of the panel. Without this arrangement the TCON would require an IC and connectors to transmit on 4,560 lines!


CTV-45 77

LCD PANEL

VIDEO PROCESS

LVDSTRANSMITTER

LVDSRECEIVER

TIMINGCONTROL

GATE DRIVERS

SOURCE DRIVERS

PANEL B+

TCONBU1

FIGURE 8-4LCD PANEL DRIVE

Panel FailuresThe key to good troubleshooting when video quality issues are involved is the understanding what type of distortions cannot be generated by the panel. The loss of an entire color is highly unlikely. The LVDS transmitter does not handle the RGB data as groups. The data (along with sync and clock) is distributed among 6 separate transmission lines for an 8-bit panel. A 10-bit panel uses 12 transmission lines. If one of these lines fails the result is random, multiple colored lines appearing on the screen. Distortions caused by the panel will be stationary and, in almost all cases, will consist of a single line or multiple lines in a repetitive pattern. Any distortion that is not stationary (flying color spots, loss of detail, etc.) is being generated by the video process circuits on the B board.Although the TCON board is considered part of the LCD panel, we will focus on the panel itself and discuss TCON failures separately since it generates symptoms that are quite distinguishable from panel issues. Panel failures fall into 2 different categories: Physical and electrical.

Physical FailuresThe most obvious failure is physical damage to the panel. This can appear as a small cluster of damaged pixels or a complete shattering of the panel glass. Another physical failure may appear as a single or several lines running vertically or horizontally across the screen. The lines may be brightly lit or dark. This is caused by a failure of the flexible printed circuit where it is bonded to the panel edge. This is known as a tab bond issue. Do not confuse this with multiple vertical lines across the screen that are of the same color. This is electrical and usually caused by the TCON board. Figure 8-5 illustrates some examples of tab bonding issues.

Electrical FailuresThere are multiple drive IC’s located along the top and side of the panel to “de-multiplex” the data for all of the rows and columns of pixels. If one of these IC’s fails there will be a cluster of missing information on the screen. The second photo in Figure 8-5 contains an illustration of a panel with such a failure.


CTV-45 78

TAB BOND AND DRIVE IC FAILURE

UPPER TAB BOND FAILURE

UPPER TAB BOND FAILURE

SIDE TAB BOND FAILURE

FIGURE 8-5LCD PANEL FAILURES


CTV-45 79

TCON FailuresFailures of the TCON circuit can cause a variety of symptoms varying from evenly spaced multiple vertical lines of the same color, fixed random patterns, colored blotches, or the complete loss of video. A complete failure of the TCON is difficult to determine since there is nothing on the display to help troubleshoot and has the same symptoms as a complete video process failure on the B board. A procedure to help in diagnosing this failure will be covered shortly.

Figure 8-6 contains several photos of symptoms caused by a failure on the TCON board. Note the fixed and symmetrical lines in the first 3 photos. This is a classic timing IC failure on the TCON board. The fourth photo is interesting. Another task performed on the TCON board is gamma correction. The correction is performed in defined zones across the entire panel. The data is stored in an on-board EEPROM. If this data is corrupted for whatever reason, one or more of the zones will exhibit a severe white balance issue.

FIGURE 8-6SAMPLES OF TCON FAILURES


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Troubleshooting a “Dead” TCON

This is a tough one. Fortunately, most of the 2007 Sony models now monitor the TCON for communications and will shut down with a diagnostics indication. In units that do not have this feature you will experience the same symptom as a complete video process failure (no on-screen graphics, no video, but audio is OK). Based on data gathered from our panel refurbishing group, about 10 to 15% of TCON failures cause a no video condition.If a customer complains of no video from any source you will be asked to bring a B board to the location since that is the most likely component to fix the problem. What if you install the board and still have no video? Did you receive a defective B board? Did you overlook any other symptoms? Make sure you have audio. This is critical. There have been numerous issues of technicians troubleshooting older models in which the ATI decoder IC for digital channels is located on a separate board (QM or Q-Box). When this decoder fails, it kills all video and audio. The technician changed several parts based on a no video condition and did not bother to check for the presence of audio. If it is verified that audio is present, the following procedure can help isolate a defective TCON in most cases.

Warning: Do not attempt to check for data or voltages on the LVDS connector at the TCON. This advice has been circulating around and is not recommended. In Figure 4 a picture of the LVDS connector is shown. In order to take a reading from one of the pins, you must insert your probe between a narrow area that is shielded and at ground potential. Several of the pins contain B+ for the TCON and panel. It is very easy to short one of these pins to ground and if it is a B+ line it is guaranteed you will be replacing a B board whether or not it was the original cause of the problem. The LVDS connector is shown in Figure 8-7.

RELEASE TABS

FIGURE 8-7LVDS CONNECTOR


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If the TCON is receiving B+ and functioning properly, the timing circuits are waiting for RGB data to allocate to the proper pixel. When a video processor failure occurs, there is simply no data being sent to the TCON and it does exactly what it is supposed to do: Keep all of the pixels dark.One trick that works rather well is to partially disconnect the LVDS connector from the TCON board while the unit is running. Do this very carefully! Both sides of the connector have release tabs that must be squeezed inward to release the connector. I have performed this over 30 times to the same television without and damage to the connector or electrical circuits. Release the connector and carefully pull it partially out of the socket being careful not to pull one side out much further than the other. Too much skewing can damage the connector and possibly cause a short on the B+ line. The idea is to remove some of the LVDS data entering the TCON.

If the TCON is functioning the loss of data will cause the timer circuits to generate random patterns. These patterns may appear as a brief colored horizontal bar or continuously active random lines covering the entire screen. The type of response you get will depend on the panel design and how much LVDS data you have removed. Sometimes a momentary line will flash on the screen, other times the screen will fill with random patterns. If you don’t see any response, try plugging the connector back in and pulling it out one more time watching the screen very closely for any reaction. Figure 5 illustrates 2 different types of patterns generated by the same unit.

If you are able to generate any response on the screen, the TCON is most likely OK. A TCON that has completely failed (causing a no video condition) will not produce any pixel lighting on the screen.

SINGLE MOMENTARY LINE

MOVING RANDOM PATTERNS

FIGURE 8-8SAMPLE REACTIONS TO LVDS LOOSENING


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DLNA Overview

For many years there was talk about how the entire home would one day be on a network system. The customer would be able to watch TV, access music files, browse the internet, along with controlling devices such as lighting and heating/cooling and so on. Although systems have been developed for many years they were proprietary in nature and quite expensive to install.

Another issue is that the television is primarily considered a separate entity whose function is to watch movies and TV programs along with gaming devices. The computer served its own function of running programs and accessing the internet.

As the turn of the century came and went, consumers became exposed to new devices to store their audio, video and picture content. Prior to the year 2000 very few homes had many of the products we see today such as digital audio players, digital camcorders, PDA’s, multi-media cell phones etc. Although the personal computer interfaces quite well with all of these devices customers found it to be a hassle to plug and unplug the devices and organize the material on their home computer. Since the consumer’s expectations were not being fulfilled, the concept of interoperability among these devices needed to be addressed. The introduction of wireless networks was a promising technology but there was still a problem with interconnecting these devices. A common method of communication and detection was needed.

The Digital Living Network Alliance (DLNA) appears to have resolved this issue. DLNA provides an answer to the marketplace by providing a seamless environment where PC, CE and mobile devices can communicate and transfer information by providing the standards for this to happen. The customer will be able to manage and distribute pictures, video and audio content to television and monitor devices along with audio systems. By following these guidelines, manufacturers can design products that function in this platform.

Virtually all of the key leaders in the PC, CE and mobile device industry have jumped on board to support DLNA. This has created the guidelines for physical media, formats, network transport, streaming protocols and, of course, digital rights management. As long as manufacturers produce appealing products, and the DNLA standards evolve with the improvements and changes, the promising world of communication among consumer devices appears to be a reality. For more information, visit http://www.dlna.org.

http://www.dlna.org

http://www.dlna.org


CTV-45 83

DLNA connectivity is provided in selected Sony televisions for the 2008 model year. As of this writing it is available on the Z4100 series which includes a 40 and 46-inch model and also the XBR6 models available in 40, 46, and 52-inch. The XBR7 and XBR8 high-end models being released this fall will also have the DLNA feature. An RJ45 Ethernet port will be available at the rear of the unit to allow a connection to a home network.

Any file sharing will require the use of a DLNA compliant system and this requirement can be met with software. There are numerous choices of software available. Most are available at no charge. Some require a one-time fee and others a monthly service fee.

Although DLNA allows the sharing of video, audio and pictures, the 2008 models containing this feature will only allow for sharing of photos. Once copyright protection issues are worked out we should see future models supporting movie and audio file content. Another feature that will become common is the ability of consumer products to check for any available software updates. This can be done manually or automatically checked for on a regular basis and notify the customer of a new software version. The customer can choose to install a newer version or the file may be written to “force” install an update.

High-speed internet access is changing the way we receive our media content allowing yet another method of viewing movies and audio aside from the traditional cable and satellite sources. DLNA looks to be a promising feature to take advantage of this technology.

and i.Link are trademarks of Sony Electronics

2007 Sony Electornics, Inc.SEL Service Company

16530 Vill EsprilloNational Training Dept. MZ3215

San Diego, CA 92127Reproduction in whole or part without written permission is prohibited. All rights reserved

CTV450508 8/12/08

lcd dissamble

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