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HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 1/12 December 11, 2016
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
D/N: AN0444E
Introduction The HOLTEK HT66FB576/574/572 RGB LED 8-bit USB Flash MCUs are specially
designed for RGB LED product applications as they have the ability to control up to
128/64/40 RGB LEDs respectively in a matrix scan configuration. Providing stable
constant current outputs for driving the RGB LEDs directly, these devices also include a
set of hardware circuits which can automatically calculate the LED PWM duty values and
support a display frame refresh rate of up to 450Hz. These features allow users to
develop their application in a rapid way, ensure superior LED display effects and also
reduce product costs since there is no need for external PWM driver ICs. This application
note mainly introduces the related registers and operation procedures of the
HT66FB576/574/572 RGB LED PWM function.
Functional Description The HOLTEK HT66FB576/574/572 RGB LED 8-bit USB Flash MCUs provide users with
a set of RGB LED PWM registers including a LED PWM constant current source control
register CCS and up to 112 relevant LED PWM control registers such as LCIO0, LCIO1
and etc. These devices also provide two LED PWM dedicated data memory sections
which are used to record the data associated with the hardware automatic calculation.
Additionally the COM7~COM0 and CCO47~ CCO0 ports, which are LED PWM dedicated
output pins, are provided to help users rapidly implement their applications.
Part No. VDD Program Memory
Data Memory
LED PWM Memory
Data EEPROM I/O RGB LED
PWM Max RGB
LED Support
HT66FB572
2.2V~5.5V
8K×16
1024×8
512×8
256×8
34 15 40
HT66FB574 16K×16 512×8 38 24 64
HT66FB576 32K×16 1024×8 52 48 128
HT66FB576/574/572 Selection Table
This section will give descriptions of the constant current source registers and LED PWM
function control registers, the RGB LED PWM architecture, LED PWM automatic mode
and manual mode operations, LED PWM waveforms as well as a hardware circuit
description. For the purpose of this application note the following description will take the
HT66FB576 device as an example.
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 2/12 December 11, 2016
RGB LED PWM Architecture Description
The HT66FB576 RGB LED PWM functional architecture, which is shown in fig.1, is
composed of 16 RGB LED PWM modules, a two pages LED PWM RAM, a register
transfer unit and an LED COM output unit.
Each RGB PWM module includes four PWM control circuits used for the Colour A/Colour
B/Colour C as well as intensity control. Colour A, Colour B and Colour C can
corresponded directly with Red/Green/Blue (RGB) colours according to the users’
requirements. The device provides 3(n+1) PWM CCO outputs where n is determined by
the selected module number. A maximum of 48 sets of 6-bit PWM CCO outputs can
provide up to 26M(218) colours. The PWM modules clock source frequency can be
selected to be either 12MHz, 16MHz or 24MHz, selected using the PWMCK[1:0] bits in
the PWMCTL0 register.
The PWM intensity control frequency is 64 times that of the colour PWM frequency. For
each colour level set by the duty cycle of the colour PWM signals, its brightness can be
adjusted by modulating the PWM signal intensity. This allows the colour level to remain at
the same ratio for red, green and blue, while dimming or increasing the overall brightness.
The LED PWM Waveform section will give more information.
The LED COM output unit outputs the external enabling COMm control signals, which are
used together with the PWM CCO outputs in a matrix scan method to implement
(m+1)×(n+1) RGB LED applications.
There is a two page 512-byte LED PWM dedicated data memory, LED_RAM_A and
LED_RAM_B. These two data memory sections can be alternately used for directing the
hardware display operations. When one memory section is being used, the data for the
next frame display can be written into the other memory, thus greatly reducing the
demands on firmware execution speed. LED_RAM_A is located at 80H~FFH in Sector 8
~ Sector B of the Data Memory while LED_RAM_B is located at 80H~FFH in Sector C ~
Sector F. Together with the LED colour and brightness transfer unit and the related
registers, the hardware can implement automatic calculation of the PWM duty cycle.
There are two interrupts, UDINT and LEDINT which can be used during the program
design procedure. The hardware automatically accesses the LED PWM memory data
and when a frame of data is completed, it will generate an LEDINT interrupt signal.
The hardware circuit also provides a function which can automatically increase or
decrease the PWM duty value to achieve various RGB LED display effects, such as that
for breathing lamps, colourful light automatic transformation etc. thus reducing the
firmware workload. In PWM Up or Down mode, which is decided by the UDS bit, the
PWM duty in the LED RAM is increased or decreased by the offset value. If the duty value
reaches the HLMD (high limit) or LLMD (low limit) register value, a UDINT interrupt signal
will be generated.
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 3/12 December 11, 2016
Module 0
Module n
6-bit PWM
Intensity
/64
LEDRAM_A
LEDRAM_B
MnCCE
LED Color and Intensity PWMTransfer Unit
HLMOS & LCIO & LFCR Register
UDS & COMDIR & LDCOME & CCOLPO & LDCOM[2:0]
fPWM_16M
fPWM_24M
fPWM_12M
MnCBE
MnCAELMnCAR [5:0]
MnIE
LED COM Output
PWMN[1:0]
6-bit PWMColor C
PWMControl
6-bit PWMColor B
PWMControl
6-bit PWMColor A
PWMControl
RGB3n
PWMILM & PWMALM & PWMBLM & PWMCLM & LLMD Register
PWMIHM & PWMAHM & PWMBHM & PWMCHM & HLMD Register
LMnCBR [5:0]
LMnCCR [5:0]
PWMN[1:0]
PWMN[1:0]
LMnIR [5:0]
RGB3n+1
RGB3n+2
PWMCK[1:0] RAMCK[1:0]
LEDCOM m
LEDRegister A
LEDCOM 0
LEDCOM m
LEDRegister B
LEDCOM 0
COMm
LEDINT(To LED PWM interrupt)
UDINT(To LED Up/Down interrupt)
LED RAM
SFR Fig1. RGB LED PWM Block Diagram – n=0~F, m=0~7
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Constant Current Source and LED PWM Control Register Description
The HT66FB576 RGB LED PWM function includes both constant current source and LED
PWM control functions, whose registers are all located in Data Memory Sector 2. The
constant current function can be controlled by the CCS register to output a constant current.
The LED PWM function can operate in two modes, manual mode and automatic mode,
which are selected and configured by the PWMCTL0 and PWMCTL1 registers.
In manual mode, the LMnIR, LMnCAR, LMnCBR and LMnCCR registers are used to
control fixed PWM duty outputs.
In the automatic mode, using the prestored data in the LED_RAM_A and LED_RAM_B
memory in Sector 8 ~ Sector F, the hardware increases or decreases the duty values of
the RGB colour and intensity PWM. In the Value Up and Down modes, the duty values
are compared with the high limit and low limit values controlled by HLMD&LLMD registers
and the values of their respective high/low limit register pairs, PWMILM & PWMIHM,
PWMALM & PWMAHM, PWMBLM & PWMBHM and PWMCLM & PWMCHM and the
offset values which are defined in the LCIO0, LCIO1 and LFCR registers. The RACmE0 &
RACmE1, RBCmE0 & RBCmE1 registers can enable or disable the corresponding RGB
LED outputs.
The HT66FB576 constant current source and LED PWM control registers are listed in the
following table. Refer to its Data Sheet for more details.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 LCIO0 CBPWM3 CBPWM2 CBPWM1 CBPWM0 CAPWM3 CAPWM2 CAPWM1 CAPWM0 LCIO1 IPWM3 IPWM2 IPWM1 IPWM0 CCPWM3 CCPWM2 CCPWM1 CCPWM0 LFCR LFCR7 LFCR6 LFCR5 LFCR4 LFCR3 LFCR2 LFCR1 LFCR0
RACmE0 RACm7 RACm6 RACm5 RACm4 RACm3 RACm2 RACm1 RACm0 RACmE1 RACmF RACmE RACmD RACmC RACmB RACmA RACm9 RACm8 RBCmE0 RBCm7 RBCm6 RBCm5 RBCm4 RBCm3 RBCm2 RBCm1 RBCm0 RBCmE1 RBCmF RBCmE RBCmD RBCmC RBCmB RBCmA RBCm9 RBCm8
LMnIR MnIE - MnID5 MnID4 MnID3 MnID2 MnID1 MnID0
LMnCAR MnCAE - MnCAD5 MnCAD4 MnCAD3 MnCAD2 MnCAD1 MnCAD0
LMnCBR MnCBE - MnCBD5 MnCBD4 MnCBD3 MnCBD2 MnCBD1 MnCBD0
LMnCCR MnCCE - MnCCD5 MnCCD4 MnCCD3 MnCCD2 MnCCD1 MnCCD0 PWMCTL0 PWMN1 PWMN0 PWMCK1 PWMCK0 LDCOME LDCOM2 LDCOM1 LDCOM0 PWMCTL1 UCLPD CCOLPO COMDIR UDS D3 D2 PWMGE PSEL PWMILM - - ILM5 ILM4 ILM3 ILM2 ILM1 ILM0
PWMALM - - CALM5 CALM4 CALM3 CALM2 CALM1 CALM0
PWMBLM - - CBLM5 CBLM4 CBLM3 CBLM2 CBLM1 CBLM0
PWMCLM - - CCLM5 CCLM4 CCLM3 CCLM2 CCLM1 CCLM0
PWMIHM - - IHM5 IHM4 IHM3 IHM2 IHM1 IHM0
PWMAHM - - CAHM5 CAHM4 CAHM3 CAHM2 CAHM1 CAHM0
PWMBHM - - CBHM5 CBHM4 CBHM3 CBHM2 CBHM1 CBHM0
PWMCHM - - CCHM5 CCHM4 CCHM3 CCHM2 CCHM1 CCHM0 HLMOS HMOS3 HMOS2 HMOS1 HMOS0 LMOS3 LMOS2 LMOS1 LMOS0 HLMD - - HLMD5 HLMD4 HLMD3 HLMD2 HLMD1 HLMD0
LLMD - - LLMD5 LLMD4 LLMD3 LLMD2 LLMD1 LLMD0
CCS CCEN MC2 MC1 MC0 - - CCG1 CCG0
Constant Current and LED PWM Control Register List - n=0~F, m=0~7
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 5/12 December 11, 2016
LED PWM Automatic Mode Operation Description
Operating in the LED PWM Automatic Mode, the device will use the following registers
LCIO0, LCIO1, LFCR, RACmE0, RACmE1, RBCmE0, RBCmE1, PWMCTL0, PWMCTL1,
PWMILM, PWMALM, PWMBLM, PWMCLM, PWMIHM, PWMAHM, PWMBHM, PWMCHM,
HLMOS, HLMD and LLMD. A two page 512-byte LED PWM dedicated Memory known as
LED_RAM_A and LED_RAM_B are used for the automatic mode operations. The PWM
output control flow chart is shown below.
The number of LED COM outputs is determined by the LDCOM[2:0]( PWMCTL0 Bit 2~0)
bits. The used COMm ports must be in continuous numbers starting from COM0. For
example, if three COM outputs are needed, then they must be output from the
COM0~COM2 ports. Every 3 CCO outputs as a group controls an RGB LED, e.g. CCO[2:0]
and CCO[5:3] each can control an LED. The points mentioned above should be noted
during circuit design.
The required PWM duty cycle value and PWM mode control data can be written into the
LED_RAM_A and LED_RAM_B memory first after which the PSEL(PWMCTL1.0) bit can
be setup to select which Data Memory is to be used in the Automatic mode. If the other
memory is selected as the data memory for the next frame, the hardware will continue to
operate with the data in the current memory until the data at the end address is processed,
that is until the current frame has completed. After this the hardware will process the data in
the selected LED_RAM memory.
The following content will illustrate the data format in the LED PWM dedicated Data
Memory, and the relationship between the PWM duty and the offset value in the value up,
value down and breathing modes.
Configure how many LED COM output by LDCOM[2:0]
Start
Configure PWM source by PWMCK[1:0]
End
Configure PWM output number per each COM by PWMN[1:0]Configure how may LED frame to update LED RAM data by LFCR registerConfigure the corresponding Color PWM and Intensity PWM offset data by LCIO0, LCIO1 & HLMOS RegisterConfigure the Limit register HLMD, LLMDConfigure the corresponding Limit register PWMxHM, PWMxLM where x= I, A, B & C in order to decide which offset register LCIO0 & LCIO1 or HLMOS is in operation.Store application data to LED RAMConfigure which LED RAM and PWM enable Register is in action by PSEL bit
Enable LED hardware Unit by set LDCOME bit and PWMGE bit
STEP 1
STEP 2
STEP 3
STEP 4
PWM Output Control Flow Chart
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 6/12 December 11, 2016
Flowchart Description
STEP1: Configure the PWM clock source frequency by setting the PWMCK[1:0] bits
STEP2: Configure how many LED COM outputs are used using the LDCOM[2:0] bits
STEP3: Settings
(1) Configure the PWM cycle output number per each LED COM using the
PWMN[1:0] bit – a recommended value is 10, i.e. one time PWM output per
LED COM.
(2) Configure the interval regarding how many LED frames are between updating
the PWM values in the automatic mode.
(3) Setup the corresponding Colour and Intensity PWM offset values using the
LCIO0, LCIO1 and HLMOS registers.
(4) Setup the Colour and Intensity limit values by setting the HLMD and LLMD
registers.
(5) Setup the corresponding duty range using the PWMxHM and PWMxLM
registers where x=I, A, B or C
(6) Write the required data into the LED PWM dedicated data memory.
(7) Select the LED PWM memory to be used by hardware using the PSEL bit.
STEP4: Set the LDCOME and PWMGE bits to enable the hardware unit for the LED
PWM automatic calculation.
In the automatic mode, the LED PWMs can control the RGB LEDs in a matrix scan
method and generate 3×(n+1) SEG and (m+1) COM outputs in total. The LED PWM
timing diagram is shown below.
An LED frame is a period time that the hardware outputs are low (if the COMDIR bit is 0)
from COM0 to COMm. When COMm is low, the CCO outputs the corresponding PWM
duty cycle according to the related register settings and the data in the LED PWM
dedicated Data Memory.
COM0
LED COMTime Slot
LED frame Interrupt request flag
EnMble tOe corresponding PWM register Mnd output PWM cycle
COM 1
COM m
COM m-1
LED COM Cycle
COM 1
COM m
COM m-1
COM 0
CCO[2:0]
CCO[5:3]
CCO[47:45]
About 10us between COMm-1 Mnd COMm for Non-overlMp
T
T
LED PWM Timing Diagram - m=7
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
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LED PWM Dedicated Memory Data Format Description
For the LED PWM automatic mode operation, the device provides two pages of an
512-byte LED PWM dedicated data memory, known as LED_RAM_A and LED_RAM_B,
which are used to record the PWM duty data and mode status. Each memory section
stores 4×(n+1)×(m+1) bytes of data. The LED_RAM_A is located at 80H~FFH in Sector 8
~ Sector B of the Data Memory while the LED_RAM_B is located at 80H~FFH in Sector C
~ Sector F. Each LED RAM is subdivided into 8 columns, Column0~Column7. The LED
RAM allocation is shown as follows.
The data stored in the LED RAM are in units of bytes and the definition of each byte is as
follows:
Bit 7~6 Define the PWM mode
00: Output fixed PWM value
01: After setting the PWM duty output, the duty value will increment or
decrement according to the corresponding offset value. The result will be
stored back to the LED RAM. The increment or decrement operation is
determined by the UDS (PWMCTL1.4) bit.
10: The PWM value up in the breathing mode plus the corresponding offset
value is stored back into the LED Data Memory.
11: The PWM value down in the breathing mode minus the corresponding offset
value is stored back into the LED Data Memory.
In the breathing mode, if the duty value in the LED Data Memory is increased to
the high limit value set by the HLMD[5:0] bit field, the hardware will automatically
change the PWM mode to “the PWM value down in breathing mode”. Similarly,
if the duty cycle data in the LED Data Memory is decreased to the low limit value
set by the LLMD[5:0] bit field, the hardware will automatically change the PWM
mode to the “PWM value up in breathing mode”.
Bit 5~0 Define PWM duty initial value
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
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PWMI_CmM0PWMCA_CmM0PWMCB_CmM0PWMCC_CmM0
PWMI_CmMFPWMCA_CmMFPWMCB_CmMFPWMCC_CmMF
Column 0
Column 1
Column n
Column 6
Column 7
Column 0
Column 1
Column 6
LED_RAM_A
LED_RAM_B
Column 7
Data format
Start address : RAM Sector 8 [80H]
End address : RAM Sector B [FFH]
Start address : RAM Sector C [80H]
End address : RAM Sector F [FFH]
Cm= C0,C1,C2…….C7
LED RAM Allocation
In each Column, there are 4× (n+1) bytes of data which is recorded in the following way.
PWM Column m data: Store the mode and the duty data of Colour A, Colour B, Colour C
and the intensity PWMs, which are used for the COMm and Module n controlled RGB
LEDs.
PWMI_CmM0: The duty values of the intensity PWM for the COMm and Module 0
controlled RGB LEDs.
PWMCA_CmM0: The duty values of the Colour A PWM for the COMm and Module 0
controlled RGB LEDs.
PWMCB_CmM0: The duty values of the Colour B PWM for the COMm and Module 0
controlled RGB LEDs.
PWMCC_CmM0: The duty values of the Colour C PWM for the COMm and Module 0
controlled RGB LEDs.
:
:
PWMI_CmMF: The duty values of the intensity PWM for the COMm and Module F
controlled RGB LEDs.
PWMCA_CmMF: The duty values of the Colour A PWM for the COMm and Module F
controlled RGB LEDs.
PWMCB_CmMF: The duty values of the Colour B PWM for the COMm and Module F
controlled RGB LEDs.
PWMCC_CmMF: The duty values of the Colour C PWM for the COMm and Module F
controlled RGB LEDs.
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 9/12 December 11, 2016
Value Up /Down and Breathing Mode PWM Duty and Offset Value Description
In LED PWM automatic mode of value up, value down or breathing mode applications,
the hardware will increment or decrement the offset data from the PWM duty value and
then write the results back into the corresponding LED RAM. The relevant registers
include PWMxLM(x=I/A/B/C), PWMxHM(x=I/A/B/C), HLMOS, HLMD and LLMD.
In order to meet the needs of different LED displays, the device provides three ways to
setup the offset value, based on which range the PWM duty value is in to change the
variations of the colour and the intensity value. It offers users greater flexibility in
applications which are required to change the LED display colour and brightness. The
following figure illustrates the offset value settings for different PWM duty values.
The following conditions must be noted when setting up the offset data to increment or
decrement the PWM duty values of the colour PWMs or intensity PWM. Since the hardware
has no mistake-proof function, the relationship between these values should be noted.
(1) When the PWM duty values for Intensity, Colour A/B/C are between HLMD[5:0] and
PWMxHM[5:0](x=I/A/B/C), their offset values can be set to the same value as
HMOS[3:0]. This allows the brightness and the colour to change smoothly with a
smaller offset value when the colour and the intensity are both weak.
(2) When the PWM duty values for Intensity, Colour A/B/C are between the
PWMxHM[5:0] (x=I/A/B/C) and PWMxLM[5:0] (x=I/A/B/C), the offset values can be
set independently using their respective offset value setting bit field IPWM[3:0],
CAPWM[3:0], CBPWM[3:0] and CCPWM[3:0]. This is commonly used in the main
display phase, where the degree of the brightness and colour change can be set
based on the application requirements.
(3) When the PWM duty values for Intensity, Colour A/B/C are between the
PWMxLM[5:0] (x=I/A/B/C) and LLMD[5:0], their offset values can be set to the same
value as LMOS[3:0]. This allows the brightness and the colour to change smoothly
with a larger offset value when the colour and the intensity are both strong where a
small change is difficult to notice.
PWM duty Low Limit data for Intensity, Color A/B/C by LLMD[5:0]
PWM duty High Limit data for Intensity, Color A/B/C by HLMD[5:0]
PWM duty High data for Intensity& Color A/B/C duty offset modify by PWMxHM[5:0](x=I/A/B/C)
PWM duty Low data for Intensity& Color A/B/C duty offset modify by PWMxLM[5:0](x=I/A/B/C)
Duty offset of Intensity& Color A/B/C = HMOS[3:0]
Duty offset of Intensity=IPWM[3:0]Duty offset of Color A =CAPWM[3:0]Duty offset of Color B =CBPWM[3:0]Duty offset of Color C =CAPWM[3:0]
Duty offset of Intensity& Color A/B/C = LMOS[3:0]
PWM Duty Value vs. Duty Offset
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LED PWM Manual Mode Operation Description
If the LDCOME (PWMCTL0.3) bit is set as ‟0”, the LED PWM will operate in the manual
mode and its relevant registers including LMnIR, LMnCAR, LMnCBR, LMnCCR(n=0~F),
PWMCTL0 and PWMCTL1 must be setup correctly. In the manual mode, users need to set
the PWM duty value and disable/enable the PWM outputs using the application program.
The COMm output function should be configured by the related pin-shared I/O registers.
In the manual mode, the LED_RAM memory and some registers related to the automatic
mode are invalid.
LED PWM Waveform Description
The LED PWMs includes the intensity PWM and the colour PWMs. The frequency of the
intensity PWM is 64 times that of the colour PWM. For each colour level set by the duty
cycle of the RGB colour PWMs, its brightness can be adjusted by modulating the intensity
PWM duty cycle. This allows the colour level to remain at the same ratio between red,
green and blue, while reducing or increasing the overall brightness.
The following example shows a colour PWM waveform, an intensity PWM waveform and
the output RGB PWM waveform. In this example, during each LED COM cycle, there are
two PWM cycles. The colour PWM duty is 2 while the intensity PWM duty is 1, which
ensure that during the colour PWM duty cycle, there is an intensity PWM for brightness
adjustment. This allows the colour level to remain at the same ratio between red, green
and blue when the brightness changes.
Module 6-bit Color PWM(Duty Value=2)
Module 6-bit Intensity PWM
Module RGB PWM Output Waveform
Module6-bit Color PWM period
1 64 164
Module 6-bit Intensity PWM period
Color PWM duty cycles
Intensity PWM duty cycles=1
COM Output Waveform(each COM = 2 PWM cycle)
Module 6-bit Intensity PWM period
Intensity PWM duty cycles=164
Module RGB PWM Output Waveform
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 11/12 December 11, 2016
Hardware Circuit Unit Description
The hardware circuit unit related to the LED PWM function includes the CCVDD, CCVSS,
LEDVSS, REXT, COM7~0 and CCO47~0 pins. The COM7~0 & CCO47~0 pins are for the
COM & SEG outputs for the RGB LED matrix scan. The REXT resistor is required for
constant current control with a recommended value of 1.8 kohm. The constant current value
which is 4-level selectable by the CCG[1:0] bits can be fine-tuned using the REXT resistor.
The CCVDD& CCVSS pins are the power pins for the constant current control circuit.
For applications, a capacitor should be connected between the power pins. This should
be located as close to the device as possible to maximise power decoupling. With regard
to interference between CCVDD and CCVSS, it is recommended to consult the following
application circuit. In the circuit the COM outputs are active low (COMDIR=0).
VDD
VDD
8 X 16 RGB LED
HT66FB576
RGB LED Matrix Circuit
REXT
VDD
PMOSx8VDDAVDD
VSSAVSS
UBUS
RESET
LEDVSSCCVSS
REXTCCVDD
CCO0
COM0
COM7
CCO47
..
.VDD
. . . . . . .
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
CCO0CCO1CCO2
. . . . .
..
.
CCO3CCO4CCO5
CCO6CCO7CCO8
CCO39CCO40CCO41
CCO42CCO43CCO44
CCO45CCO46CCO47
..
..
..
..
..
..
..
..
CCO0CCO1CCO2
CCO3CCO4CCO5
CCO6CCO7CCO8
CCO39CCO40CCO41
CCO42CCO43CCO44
CCO45CCO46CCO47
. . . . . . .
. . . .
..
..
..
..
..
..
..
..
CCO0CCO1CCO2
CCO3CCO4CCO5
CCO6CCO7CCO8
CCO39CCO40CCO41
CCO42CCO43CCO44
CCO45CCO46CCO47
Recommended Application Circuit
HT66FB576/574/572 RGB LED PWM Function Application Guidelines
AN0444E V1.00 12/12 December 11, 2016
Conclusion This application note has summarised some considerations and provided advice on using
the HT66FB576 RGB LED PWM function to assist users to use the RGB LED PWM
function more flexibly and develop their products as rapidly as possible.
Versions and Revision Date Author Issue and Revision
2016.09.12 王冠中 First Version
Reference Files For more information, refer to the Holtek official website http://www.holtek.com.tw.
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