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INTHISISSUEPAGE1

Register for the 10th Annual MASTERs Conference

PAGE2

Bit Bashing; Double Your Voltage, Double Your Fun — A Microchip Comparator Gets It Done

PAGE3

Production Programming Service through microchipDIRECT

Microchip is Hiring!

PAGE4-5

10 Key Elements of the Aggregate System

PAGE5

Selecting the Right ADC

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Recommended Usage of Microchip’s SPI Serial EEPROMs

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High-Performance PWM for Motor-Control, Lighting and Power-Conversion Applications

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The Role of Digital Control in Power Supplies

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WebSeminars

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What’s New in Microchip Literature?

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Web Site Highlights

INTHISISSUE

MASTERs Registration

ends June 23! Formoreinformationvisit:http://www.microchip.com/MASTERs

Registration is now open for the 10th Microchip Annual Summer Technical Exchange Review. Don’t miss this opportunity to learn about new products and technologies. The Microchip Annual Summer Technical Exchange Review (MASTERs) Conference is a bi-directional exchange of technical information between the technical work force at Microchip and our strong technical partners, including consultants, customers, third parties, distributors, field application engineers and design houses. MASTERs is an in-depth, highly technical conference structured to meet the needs of today’s design engineers.

Are you looking for solutions to embedded control challenges or in-depth education on Microchip’s products? Are you a design engineer or engineering manager looking for solutions and wanting to interface with Microchip architects and developers? Students graduating from the MASTERs program are equipped to go out and use Microchip products to their full advantage. Certificates are awarded upon completion of the conference.

This year’s Conference is larger and more diverse than ever with 94 different classes -- more than half of them are hands-on. Typical of this year’s new hands-on classes is: “1042 CAL: Using Communication Application Libraries with Microchip’s 16-bit Microcontrollers.” This class is designed for engineers who want to get their hands on some of the libraries available for Microchip’s 16-bit products. Using the Explorer 16 demo board and the PICtail™ Plus daughter board connector, you can

explore solutions for IrDA® protocol, Ethernet & TCP/IP, speech compression, SD and CF Flash Card interface with FAT 16, and wireless networking. See first-hand how using the 16-bit libraries can help enable your applications to communicate with the outside world.

Some of the more popular classes from last year are back again with updated information such as: “1039 WCE: 802.11 for Embedded Systems.” This lecture class teaches you how to quickly develop small embedded applications that communicate using Wi-Fi® networks. Learn about the requirements, the protocols, the hardware, the software and the tricks required to implement embedded wireless LAN connectivity. The class is taught by Fred Eady, a 20-year industry veteran and author of over 100 articles in Circuit Cellar Ink magazine.

Make it a full week of technical training with the new Pre-Conference WorkshopsWorkshops for Beginners & Advanced If you’re new to Microchip, check out our pre-conference

workshops to help you get started with development tools, 8- and 16-bit architectures and more. Advanced users can select from programming, communications, mechatronics and even a 2-day embedded C programming workshop. Get a jump on your week with pre-conference workshops running Monday, July 24 and Tuesday, July 25th.

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In model aircraft parlance, kit bashing is defined as the practice of using the materials from a kit for one aircraft to build a similar, but different aircraft. So, bit bashing is the process of using the features of one or more simple peripherals to build a more complex custom peripheral.

This month’s Bit Bash: Double Your Voltage, Double Your Fun — A Microchip Comparator Gets It DoneThe focus this month is power, or rather the generation of a power supply voltage that is outside the limits of the available supply voltage. A simple technique for generating a programmable supply voltage above VDD, or below VSS is described.

The basic topology used is a capacitive doubler/inverter with a spare comparator to regulate the output of the circuit. See Figure 1.0 below.

Figure 1.0 Doubler Circuit

The source of the switching clock is the CLKOUT pin of the microcontroller, if the internal oscillator is used. This means either a 1 or 2 MHz clock. The CLKOUT drags the low side of the C1 up to VDD and down to VSS. If the C1OUT is high, then C1 is charged through D1 when CLKOUT is low. When CLKOUT goes high, the charge in C1 is then shared with C2 through D2. C2 then provides the output voltage of the circuit and after being divided by R1/R2, it is fed back to the voltage comparator.

If the divided output voltage is greater than the CVREF voltage, C1OUT goes low and the circuit no longer charges C1. If the divided output voltage is less than the CVREF voltage, C1OUT goes high and C1 is charged.

Immediately after startup, charge is built up in C2 over the course of several cycles, until the divided output voltage is equal to CVREG. When this happens, the comparator output goes low and C1 stops charging. This leaves C2 at the desired voltage and the system is stable. As current is drawn by the load and the resistor dividers, the charge in

Bit Bashing; The practice of combining peripherals, external components and firmware to create a new function, feature or peripheral (slang)

C2 is depleted and the divided output voltage falls below CVREF, resulting in the output of the comparator going back high. The comparator output stays high just long enough to replenish the charge in C2 and then it drops again. The circuit continues like this while the comparator is enabled.

The inverter configuration, shown in Figure 2.0, operates in much the same way. CLKOUT supplies current to C1 through D1 and COUT is a current sink during charging. CLKOUT then goes low and C1 balances its charge with C2 generating a negative output voltage. Due to the limitations on common mode voltage on the comparator inputs, it is necessary to tie the output voltage divider to VDD and set CVREF for its high range.

Figure 2.0 Inverter Circuit

In operation, the comparator goes low whenever the divided output voltage is greater than the voltage generated by CVREF. The energy transfer then continues until the output voltage pulls the divided output back below the CVREF voltage. So, in a manner similar to the doubler, the circuit maintains a negative voltage determined by the programming of CVREF and VDD.

In the doubler configuration, the circuit is limited to a voltage between VDD and 2 x VDD minus the forward voltages of both diodes. In the inverting configuration, the output is limited to voltages between VSS and VSS minus VDD minus the forward voltages of both diodes.

Total cost, one on-chip or external comparator, two diodes, two capacitors and two resistors. No firmware is needed to maintain the system and loading different values into CVREF changes the output voltage.

CVREF

VOUT

CVREF

VOUT

VDD

Formoreinformationconcerningtheoperationanddesignofcapacitivedoublerandinvertercircuit,seeTC7660datasheetat:

http://ww1.microchip.com/downloads/en/DeviceDoc/21465b.pdf

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IT’STIMETOCONSIDERANEWCAREERAT

MICROCHIPTECHNOLOGYINC.Microchipishiring!Thefollowingpositionsarecurrentlyavailable:Applications Engineer • Associate Engineer • CAD Library Manager • Corporate Applications Engineer • Design

Engineer • Diffusion Production Supervisor • Embedded Applications Engineer • Embedded Software Engineer

• Engineering Technician II • Failure Analysis Engineer • Field Applications Engineer • Field Applications Manager

• Field Sales Administrator • Field Sales Engineer • Human Resources Manager • Information Systems Wintel

DMZ Infrastructure Architect • Junior Planner • Layout Designer II • Lead Layout Designer • Library Design

Engineer • Logistics Coordinator/Planner • Marketing Applications Engineer • microchipDIRECT Customer

Service Rep • Principal/Staff Design Engineer • Principal Applications Engineer • Principal Applications

Engineer/Project Leader • Principal Architect • Principal Corporate Applications Engineer • Principal Design

Engineer • Principal Process Engineer • Principal Product Quality Engineer • Principal Test Engineer • Process

Engineer • Process Tech • Product Marketing Engineer • Product Marketing Manager • Production Specialist

• Publications Specialist • Regional Distribution Manager • Section Leader/Principal Test Engineer • Senior

Applications Engineer • Senior CAD Engineer • Senior Design Engineer • Senior Engineer, Marketing • Senior

Engineering Technician • Senior Equipment Tech (Wet Process) • Senior Facilities Technician • Senior Field

Sales Engineer • Senior Internet Engineer with E-commerce Focus • Senior Inventory Control Clerk • Senior

Layout Designer • Senior Marketing Communications Generalist • Senior Oracle/ SQL Server Manufacturing

Database Administrator• Senior Process Engineering Technician • Senior Product Engineer • Senior Software

Engineer • Senior Technical Editor • Senior Test Engineer • Senior/Principal Applications Engineer • Senior/

Principal Memory Product Engineer • Senior/Principal Memory Test Engineer • Senior/Principal Probe Process

Engineer • Senior/Principal Verification Engineer • Senior Software Engineer • Supply Management Analyst

I • Tactical Marketing Manager • Technical Editor • Technical Training Engineer • Test Engineer • Windows®

Systems Administrator • Yield Enhancement Engineer

Formoreinformationabouttheseandotherpositions,pleasevisitwww.microchip.com/careersorsendyourresumetoresumes@

microchip.comtoday!

www.microchip.com/careers

Looking for a low-cost service to program your PIC® microcontrollers?With no minimum order quantity required, Microchip’s Production Programming Service through microchipDIRECT is your answer!

Now you can enjoy quick and inexpensive production programming of Microchip’s P I C ® m i c r o c o n t r o l l e r s t h r o u g h microchipDIRECT.

The process is simple. Once you upload your application code into your secure FTP account, place your PIC microcontroller order through microchipDIRECT, apply the appropriate code to your order and Microchip does the rest.

Working directly with Microchip gives you more control of your project development by eliminating unnecessary steps within your design cycle and ultimately provides you with fast time to market.

Microchip’s Production Programming Service allows you to upload your application code and request verification sample orders so that you may make certain your code works properly with the associated PIC microcontrollers within your platform. Once you have completed the verification process, you can place orders through microchipDIRECT and have your PIC microcontrollers programmed with your code as part of your order.

Benefits of Production Programming through microchipDIRECT:• Seamlessly integrated

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Formoreinformationvisit:http://www.microchip.com/

Programming

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What is the Aggregate System?The Aggregate System is a comprehensive system for building exceptional corporate culture that enabled Microchip to align, integrate and unite all of the elements of the company and improve employee performance across the board, saving the company in the process.

In this month’s column, I will summarize the 10 Key Elements of the Aggregate System that we detailed in the book titled “Driving Excellence.” When you’re constructing a values-based, highly empowered, continuous-improvement culture, it’s essential to recognize the key elements that characterize a thriving Aggregate System. If the company fails to achieve each of these 10 elements, it won’t reach its full potential.

1. Inspiring Leadership:The CEO and the other leaders of the enterprise demonstrate the company’s values through their actions—practicing what they preach. This remains true independent of economic conditions. Senior executives remain highly involved in formulating strategies and decision-making, while ensuring their employees are empowered to maintain and improve their portion of the operation. The CEO tirelessly pursues the company’s vision, mission, business strategies, revenue growth, profit-and-loss, and balance sheet models, stock appreciation and so forth. The CEO rapidly reacts to changes in the business climate, continually positioning the company in anticipation of the future outlook.

2. Continuous-Improvement Culture:The continuous-improvement culture is built on employee empowerment and involvement, teamwork, communication, problem solving, innovation, merit, frugality, systems thinking, continuous learning and results-oriented pursuit of success for the customers, shareholders and employees.

3. Clear Company Values:The company clarifies how work should be accomplished by articulating its values. This provides a framework which empowered employees are to operate. The company specifies its values concerning customers, quality, continuous

improvement, employees, products and technology, cycle times, safety, growth and profitability, communication, suppliers and distributors, ethics and so forth. The company is structured and shaped around these values. They serve to guide employees’ strategies, decisions and actions.

4. Fully Aligned Strategies:All the aspects of the company are aligned to achieve its strategic formula (i.e., vision, mission, strategies, business plans, and profit-and-loss/balance

sheet models). The company is viewed as an Aggregate System in which all aspects of the enterprise are aligned and continuously improved in order to realize the strategic formula. All employees are expected and empowered to improve the enterprise, and the culture is constructed to facilitate their efforts. The strategic formula specifies what’s to be accomplished, and the company’s values represent how the work is to be performed.

5. Employees Share in the Company’s Prosperity:Alignment among the shareholders, company and employees is achieved through a combination of fixed and variable compensation (e.g., profit sharing, cash bonuses, stock ownership, etc.) provided to employees based on individual and company performance. Employees appreciate the concept of total compensation, in which each source of compensation and benefits is viewed in combination. Through variable compensation, employees share in the prosperity of the business’ up-cycles and in the sacrifices required during down-cycles.

6. Managers Serve as Role Models:Managers and supervisors diligently work to meet

commitments, achieve the desired operational goals and drive continuous improvement. The employees believe that the managers and supervisors consistently practice the company’s culture. Moreover, management consistently promotes employees who practice the company’s values. Managers, including frontline supervisors, have strong people skills, can lead and facilitate, regularly coach and remove barriers and are comfortable with empowering employees.

10 Key Elements of the Aggregate System

Continued on next page...

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7. Politics, Ego and Arrogance Not Allowed:The focus remains on the work itself, not on the personalities of the players or their desire to gain additional power. The CEO ensures that senior managers praise in public and criticize in private. Ego and arrogance are viewed as divisive to teamwork. Positive and productive team chemistry is cultivated. The traditional symbols and trappings of status and hierarchy are absent.

8. Systems Approach Utilized to Make Improvements:All aspects of the enterprise are seen as originating from an underlying system. Each system consists of input and output variables. Systems that produce undesirable results require enhancements to these variables using problem-solving techniques, statistical methods and human expertise. Teams that consist of members from various functions or areas of expertise are routinely formed to improve the company’s various systems, procedures and policies.

9. Pursuit of Excellence:Employees are able and motivated in their pursuit of excellence. Employees accept and practice the company’s values. They are results oriented, adaptable and team players. They have an appetite for continuous improvement, innovation and quality. The employees work to satisfy both internal and external customers. They thrive in an empowerment environment, which allows for greater responsibility and authority in completing assignments and making improvements. Employee morale and job satisfaction are valued, formally measured and addressed proactively by management. There is a concerted effort to promote, transfer and hire from within to advance the culture and provide career growth.

10. Engaged Board of Directors:The Board of Directors embraces the Aggregate System approach and are in full agreement with the company’s strategic formula, culture, values and compensation philosophy. The Board works as a unified team to sustain a continuity of purpose. It maintains both a shor t-term and long-term perspective on the enterprise’s status. The CEO and the Board of Directors design a compensation philosophy that aligns the interests of the employees with those of the company and its shareholders. The Board members model the company values. — Steve Sanghi, President and CEO of Microchip Technology Inc.

Continued from previous page...

Formoreinformationvisit:http://www.drivingexcellence.biz/

Selecting the Right ADCHigh-Performance, Stand-Alone A/D Converters for aVariety of Embedded Systems Applications

Selecting the most suitable A/D Converter (ADC) for your application is based on more than just the precision or bits. Different architectures are available, each exhibiting advantages and disadvantages in various data acquisition systems. The required accuracy or precision of the system puts you in a category based on the number of bits required. It is important to always design your system to allow for more bits than initially required. If an application calls for 10 bits of accuracy, choose a 12-bit converter. The achievable accuracy of a converter is less than the total number of bits available.

Depending on the system requirements, your accuracy might be better expressed in micro-volts, dB (decibels) or LSBs (Least Significant Bits). A Fast Forrier Transform (FFT) showing the frequency spectrum of a device can be useful in determining the noise performance of a given device. Many Microchip stand-alone ADCs show typical performance data for AC specifications, such as Total Harmonic Distortion (THD), Signal to Noise and Distortion (SINAD) and Signal-to-Noise Ratio (SNR).

Typically, an amplifier is required if the magnitude of the input signal is significantly lower than the full-scale input range of the ADC. However, by selecting an ADC with a higher resolution, the need for an amplifier can be eliminated.

Successive Approximation Register (SAR) converters typically range from 8 to 16 bits, while delta-sigma converters (Δ∑) can achieve an accuracy of up to 24 bits. If your application deals more with AC signals, the ADC performance can be viewed in the frequency domain using AC plots, such as the signal-to-noise ratio FFT to the right.

FormoreinformationdownloadtheAnalog-to-DigitalDesignGuideat:http://ww1.microchip.com/downloads/en/DeviceDoc/21841A.pdf

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Application Note AN1040: Recommended Usage of Microchip SPI Serial EEPROM Devices

Author: Chris Parris, Microchip Technology Inc.

INTRODUCTION

The majority of embedded control systems require nonvolatile memory. Because of their small footprint, byte level flexibility, low I/O pin requirement, low-power consumption and low cost, serial EEPROMs are a popular choice for nonvolatile storage. Microchip has addressed this need by offering a full line of serial EEPROMs covering industry-standard, serial communication protocols for two-wire (I²C™), three-wire (Microwire), and SPI communication. Serial EEPROM devices are available in a variety of densities, operational voltage ranges and packaging options.

In order to achieve a highly robust application when utilizing serial EEPROMs, the designer must consider more than just the data sheet specifications.

There are a number of conditions which could potentially result in nonstandard operation. The details of such conditions depend greatly upon the serial protocol being used.

This application note provides assistance and guidance with the use of Microchip SPI serial EEPROMs. These recommendations are not meant as requirements; however, their adoption can lead to a more robust overall design. The following topics are discussed: Input Considerations, Write-Protection Features, Power Supply, Write Enable and Disable, WIP Polling and Increasing Data Throughput.

Figure 1 (right) shows the suggested connections for using Microchip SPI serial EEPROMs. The basis for these connections are explained in other sections of this application note. Note 1: decoupling capacitor (typically 0.1 μF) should be used on VCC.

INPUT CONSIDERATIONS

It is never good practice to leave an input pin floating. This can cause high standby current, as well as undesired functionality. If a pin is left floating, it can either float low or high. Which direction the signal goes is dependant upon a number of factors, including noise in the system and capacitive coupling. Because of this, the level seen by the input circuitry is relatively random and likely to change during operation.

Such unpredictable input levels can have devastating effects on device operation. For example, Microchip’s SPI serial EEPROMs feature a HOLD pin which allows the user to suspend the clock mid-stream. If this pin were to float low (active), the device would no longer react to any clock pulses received and communication would be disrupted.

Therefore, any unused input pins should always be tied to a proper level, such as

high for an active-low input. Moreover, it is recommended that, if the microcontroller has extra, tri-state I/O pins available, connections be made to these unused inputs along with a pull-down/pull-up resistor, as shown in Figure 1. This allows for the inputs to be used at a later date simply by modifying firmware.

Although the CS pin should always be driven by the microcontroller during normal operation, it has potential for floating during power-down/power-up. As such, this pin should also have a pull-up resistor to avoid undesired commands due to noise during these conditions.

WRITE PROTECTION FEATURES

There are two different write protection schemes featured in Microchip’s SPI serial EEPROM family of devices. One for the 4 Kb and smaller devices, and one for 8 Kb and larger devices.

For the 25XX010A to 25XX040A, the WP pin acts as a normal hardware write-protect pin. That is, if the Write Protect (WP) pin is low (active), the Write Enable Latch (WEL) is cleared and cannot be set until the pin is brought high (inactive). This means that any attempted writes to either the array or the STATUS register are blocked. Note that bringing the WP pin high does not set the WEL again. Another WREN instruction is

required in order to do this.

For the 25XX080A/B and up, the WP pin acts in conjunction with the Write-Protect Enable (WPEN) bit in the STATUS register. If the WPEN bit is cleared, the WP pin is a don’t care. If the WPEN bit is set, the WP pin can be used to block attempted STATUS register writes. Note that for these devices, the WP pin has no effect on array writes, regardless of the state of the WPEN bit. Only the Block Protect (BP) bits can block an attempted write to the array on these devices. Once the BP bits have been set, however, the WP pin can be used with the WPEN bit to prevent them from being cleared, thus preventing writes to the array as well.

Forthecompleteapplicationnotevisit:http://ww1.microchip.com/downloads/en/AppNotes/01040A.pdf

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Microchip’s newest dsPIC® Digital Signal Controller (DSC) offers the performance speed of 30 million instructions per second (MIPS), self-programming capabilities via Flash memory and industrial and extended temperature ranges. The dsPIC30F6015 DSC features an advanced Pulse-Width Modulation (PWM) peripheral designed for power conversion, motor control and lighting applications, and is offered in a 64-pin TQFP package. It is ideal for applications that drive power FETs and require advanced algorithmic processing.

The dsPIC30F6015 is part of Microchip’s Motor Control and Power Conversion portfolio and was developed for customers who want a software and pin-compatible memory expansion from the dsPIC30F5015 DSC. This new device incorporates Microchip’s Enhanced Flash self-programming capability, which permits a remote upgrade to the Flash program memory, allowing code revisions in end users’ applications. Additional key features include:

• 144 Kbytes of Flash program memory, which can withstand typically 100,000 erase/write cycles and has 40-plus years of data retention over a wide operating voltage and temperature range

• 8 Kbytes of SRAM • 4 Kbytes of high-endurance EEPROM (1 million erase/write cycles typical)• 8 output PWM, complementary or independent modes, 4 duty-cycle

generators, programmable dead time• 10-bit A/D converter with up to 16 signal channels, 1 MSPS, 4 sample and

holds for simultaneous sampling and trigger option from advanced PWM• Quadrature Encoder Interface• Five 16-bit timers• Eight standard PWMs• Two of each: CAN, SPI and UART peripherals• One I²C™ peripheral

With over 70 announced 16-bit products and more on the way, you can select from two 16-bit PIC24 microcontroller families and two 16-bit dsPIC DSC families that offer compatible options across a wide spectrum of price, performance and feature sets. Common to all of Microchip’s 16-bit MCU and DSC families are: pinout compatibility, software compatibility, peripheral compatibility and common development tools — helping to minimize development time, while retaining an optimal product selection for the application.

Looking for a High-Performance PWM for Motor-Control, Lighting and Power-Conversion Applications?

What is a Digital Signal Controller?The dsPIC Digital Signal Controller (DSC) is a 16-bit (data) modified Harvard RISC machine that combines the control advantages of a high-performance 16-bit microcontroller with the high computation speed of a fully implemented DSP to produce a tightly coupled single-chip, single-instruction-stream solution for embedded systems design. Microchip’s dsPIC DSCs are offered in two families – the dsPIC30F and dsPIC33F. The dsPIC30F may be preferable for applications that favor any of the following attributes:• Wide operating voltage range (2.5V to 5.5V)• 5V operation to maximize analog noise immunity or to minimize voltage

translation logic• Lowest power consumption in the Power-down mode of operation• Integrated, high-endurance on-chip EEPROM

The 3.3V dsPIC33F family may be preferable for applications that favor any of these attributes:• Large memory configurations (Flash and/or RAM)• Low operating power consumption• Maximum performance• Lowest cost for larger memory configurations

All dsPIC30F DSCs use the same MPLAB® Integrated Development Environment (IDE) shared by Microchip’s PIC®microcontroller family. Additionally, the dsPIC30F is supported by Microchip’s high-performance development systems, including: MPLAB C30 C Compiler, MPLAB SIM 30 Software Simulator, MPLAB ICD 2 In-Circuit Debugger and MPLAB VDI Visual Device Initializer.

Formoreinformationvisit:www.microchip.com/16bit

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By Fanie Duvenhage, Microchip Technology

Supplying power to a device, board or system is by definition an analog function that is characterized with parameters, such as voltage, current and efficiency. However, the increased performance of digital control, combined with the lower cost point of low pin count, easy-to-use microcontrollers is making digital control a viable option for various functions in power supplies. The question is: which functions are better suited for digital and where is it better to stay with the proven analog methods?

While there is a big push for digital control into the main power-control loop, digital control has a broader function in power supplies. There are basically four levels of digital integration in power supplies.

Level I adds simple functions that are difficult to do with analog components. For example, a 6-pin microcontroller can provide a PWM waveform that ramps from 0% to 100% duty cycle to provide a soft-start function to the switcher circuitry.

Level II provides a secondary management function around the more traditional analog circuit. In this case, the digital controller monitors the output parameters and uses existing external controls to enhance the functionality of the power supply, but the power-control loop is still completely analog. This is accomplished using standard microcontrollers with an integrated A/D for measuring the various parameters.

Level III is a higher level of integration, with the switcher circuitry integrated on the microcontroller. The microcontroller also controls the switching and gain, although the implementation of the feedback loop is still primarily analog. This requires a more specialized digital controller with switching circuitry and various analog functions integrated onto the device.

Level IV is complete digital control, with all parameters digitized and analyzed by the controller to provide the appropriate outputs. This typically requires a DSP with high-speed A/D converters and PWM outputs.

The Role of Digital Control in Power SuppliesThe appropriate level of digital integration depends on the requirements of the design. Most of these digital-control functions center on achieving

deterministic behavior in what are sometimes very complex, interrelated designs. Digital controllers are good at making decisions and handling “what if” conditions. When statements such as, “if X voltage is higher than Y, then adjust Z,” are used to describe the circuit, it is better to get a microcontroller to perform that function. While most of the focus has been on digital control in the main power loop, this secondary monitoring of power-supply parameters and reacting to any exceptions probably accounts for most of the practical uses of microcontrollers in power supplies today.

Digital controllers are also good at sequencing events or any timing related functions. Microcontrollers run from a

clock, which makes time measurement and event execution at specified times fairly straightforward. For example, to change the overcurrent protection level during startup and then throttle it back after 20 ms can be done fairly easily with a Level II design that utilizes a low pin count microcontroller with an internal oscillator. Again, the digital-control portion fits as a complementary peripheral function to the main power supply control loop.

Once in the power supply, there are several other advantages that come with using digital controllers. Monitoring and diagnostics of the supply can now be communicated to the rest of the system. Since many of the newer microcontrollers come with data EEPROM, event counters and logs can be stored and extracted at a later stage to provide valuable information about failures and power-supply usage. The EEPROM is also valuable in storing calibration values that can be used to linearize a temperature coefficient or reduce the cost of a voltage reference.

Formoreinformationvisit:http://www.microchip.com/dsPIC

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Category Title Duration

Analog

Do I Filter Before, After or Never? 20 min

Selecting the Ideal Temperature Sensor 30 min

Predict the Repeatability of Your ADC to the BIT 20 min

What Does “Rail-to-Rail” Operation Really Mean? 20 min

Lithium-Ion Battery Charging: Techniques and Trade-offs 20 min

Techniques that Reduce System Noise in ADC Circuits 20 min

Smaller Packages = Bigger Thermal Challenges 20 min

Select the Right Operational Amplifier for Your Filtering Circuits 20 min

Amplify Sensor Signals Using the PGA 20 min

Applications

Introduction to Mechatronics and the Mechatronic Design Center 20 min

Designing Intelligent Power Supplies 30 min

Developing Intelligent Power Systems Using the MCP1630 High-Speed PWM

20 min

Emulating RS-232 Over USB Using the PIC18F4550 30 min

EMC Part 1: Introduction to Electro Magnetic Compatibility (EMC) 20 min

EMC Part 2: What is Electrostatic Discharge (ESD)? 20 min

EMC Part 3: What are Electrical Fast Transients (EFT)? 20 min

Thermistor Application for the New MCP6S9X PGA 20 min

Wireless Communication using the IrDA® Standard Protocol 20 min

Driving Lumileds LEDs with Microchip Microcontrollers 60 min

Design Considerations When Adding CANbus to Your System 20 min

Connectivity

Microchip’s ENC28J60, World’s Smallest Ethernet Controller 20 min

Serial Communications: Using the dsPIC30F I²C™ Module 30 min

Serial Communications: Using the dsPIC30F CAN Module 30 min

An Introduction to Controller Area Network (CAN) 30 min

Motor Control

dsPIC30F Quadrature Encoder Interface Module 20 min

dsPIC30F Motor Control PWM Module 20 min

AC Induction Motor (ACIM) Control Using the PIC18FXX31 20 min

Brushless DC motor (BLDC) Motor Control Using PIC18FXX31 20 min

Category Title Duration

Dev Tools

Introduction to the Signal Analysis PICtail™ Daughter Board 30 min

Basic dsPIC® DSC Development Tools 25 min

Introduction to MPLAB®SIM Software Simulator 25 min

Get Started with the 64-/80-pin TQFP Demo Board 20 min

Tips and Tricks Using MPLAB® IDE v6.61 30 min

Introduction to the MPLAB® Visual Device Initializer (VDI) 30 min

PIC10F Development Tools: Small Tools for Small Parts 30 min

Introduction to MPLAB® IDE 25 min

Introduction to Microchip’s Development Tools 25 min

Serial EEPROM Overview 20 min

dsPIC30F General Purpose Timers 20 min

dsPIC® DSC SPI Communication Module 20 min

dsPIC® DSC UART Module 20 min

dsPIC30F 12-bit ADC Module (part 1) 20 min

dsPIC30F 12-bit ADC Module (part 2) 20 min

dsPIC30F Addressing Modes (part 1) 20 min

dsPIC30F Addressing Modes (part 2) 20 min

Introduction to dsPIC30F DSP Engine and ALU 30 min

Introduction to dsPIC30F Interrupts 25 min

dsPIC30F 10-bit ADC Module (part 1) 20 min

dsPIC30F 10-bit ADC Module (part 2) 20 min

Introduction to dsPIC30F Architecture (Part 1) 20 min

Introduction to dsPIC30F Architecture (Part 2) 20 min

Introduction to dsPIC33F Architecture (Part 1) 20 min

Introduction to dsPIC33F Architecture (Part 2) 20 min

The LCD PIC® Microcontrollers, PIC18F8490/6490, with 16 Kbytes of Flash in 64- and 80-pin Packages

20 min

Introduction to the dsPIC® DSC 20 min

64 Kbyte Flash Microcontrollers in 28-/40-pin Packages; the PIC18F4620 and PIC18F2620

20 min

Introduction to the PIC18 High Pin Count and High Density Family of Devices 20 min

Control the World with the PIC10F 30 min

Peripheral Rich, Low Pin Count, PIC® MCUs with nanoWatt Technology 30 min

Microchip’s nanoWatt Technology 45 min

Products

FormoreinformationaboutLiveWebSeminarsorArchivedWebSeminarsvisit:www.microchip.com/webseminars

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MICROCHIPTECHNOLOGY’SmicroSOLUTIONSeNEWSLETTER-June2006

www.microchip.com Microcontrollers•DigitalSignalControllers•Analog•SerialEEPROMs 10

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What’s New in Microchip Literature? Click on a Document Title to view the document.

The Microchip name and logo, the Microchip logo, Accuron, dsPIC, KEELOQ, microID, MPLAB, PIC, PICmicro, PICSTART, PRO MATE, PowerSmart, rfPIC and SmartShunt are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. AmpLab, FilterLab, Migratable Memory, MXDEV, MXLAB, SEEVAL, SmartSensor and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. Analog-for-the-Digital Age, Application Maestro, dsPICDEM, dsPICDEM.net, dsPICworks, ECAN, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, Linear Active Thermistor, Mindi, MPLIB, MPLINK, MPSIM, PICkit, PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal, PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, rfPICDEM, Select Mode, Smart Serial, SmartTel, Total Endurance, UNI/O, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies.

TypeofDocument DocumentName DSnumber Available

Application Note

AN1035, Designing with HV Microcontrollers DS01035A web

AN965, Microchip Stack for the ZigBee™ Protocol DS00965B web

AN1038, Using the MCP3906’s Serial Interface to Retrieve ADC Channel Information for RMs Power Calculation

DS01028A web

Data Sheet

PIC16CR7X 28-/40-Pin, 8-bit CMOS ROM Data Sheet DS21993A web

24AA 1025/24LC1025/24FC1025, 1024K I²C™ CMOS Serial EEPROM Data Sheet DS21941C web

TC1014/TC1015/TC1185 Data Sheet DS21335D web

Erratas

PIC10F220/222 Rev. A Silicon/Data Sheet Errata DS80271A web

dsPIC30F2011/2012 Rev. A1 Silicon Errata DS80273A web

dsPIC30F3014/4013 Rev. A1 Silicon Errata DS80228D web

PIC18F24J10/25J10/44J10/45J10 Rev. A2 Silicon Errata DS80269A web

PIC24FJ128GA010 Family Rev. A2 Silicon Errata DS80275A web

Migration PIC16CR77/76 Migration DS21995A web

Product Brief PIC18F85J11 Product Brief DS39767A web

Programming Specification PIC16F88X Memory Programming Specification DS41287A web

Reference Manual Section

PIC24F Family Reference Manual, Section 29 RTCC DS39696A web

PIC24F Family Reference Manual, Section 15 Input Capture DS39701A web

PIC24F Family Reference Manual, Section 24 I²C™ DS39702A web

PIC24F Family Reference Manual, Section 2 CPU DS39703A web

PIC24F Family Reference Manual, Section 14 Timers DS39704A web

PIC24F Family Reference Manual, Section 17 10-Bit A/D DS39705A web

PIC24F Family Reference Manual, Section 16 Output Compare DS39706A web

PIC24F Family Reference Manual, Section 21 UART DS39708A web

Tips ‘n Tricks Booklet Intelligent Power Supply Design Tips ‘n Tricks DS41283A web/printed

User’s Guide

MPLAB® IDE User’s Guide DS51519B web

MCP3551 Tiny Sensor Application Demo Board User’s Guide DS51598B web

MCP3551 DM-PCTL User’s Guide DS51579C web

MCP1630 DM-NMC1 User’s Guide DS51505B web

MCP9700 DM-PCTL User’s Guide DS51542B web

TC77 DM-PCTL User’s Guide DS51484B web

PT100 RTD Evaluation Board User’s Guide DS51607A web

MCP1630 Automotive Input Boost Converter Demo Board User’s Guide DS51608A web

MICROCHIPTECHNOLOGY’SmicroSOLUTIONSeNEWSLETTER-June2006

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websiteHIGHLIGHTSDid you know….That Microchip offers many code examples for digital signal controller products?? Visit www.microchip.com/code to view the list:

Generally Speaking, EMC is defined as the ability of an electronic system to function compatibly with other electronic systems.

A system is electromagnetically compatible if: — It does not cause interference with other systems — It is not susceptible to emissions from other systems — It does not cause interference with itself.

Good EMC design practice helps avoid the needs for design rework after testing, so minimizing development cost and time-to-market.

The goal of the EMC Design Center is to share techniques to improve EMC performance, based on real world example.

The most common terms are: — EFT: Electrical Fast Transient — EMI: Electromagnetic Interference — ESD: Electrostatic discharge Every PIC® microcontroller is capable of passing IEC61000-4-4 test at 4KV.

Web Seminars EMC, part 1 EMC, part 2 EMC, part 3

EMC Newsletter EMC Newsletter First Edition EMC Newsletter-Issue 2 January 2005 EMC Newsletter-Issue 3 March 2005 EMC Newsletter-Issue 4 May 2005 EMC Newsletter-Issue 5 August 2005 Subscribe to the EMC Newsletter

Brochure: Robust Product Solutions BrochureApplication Notes: AN943 — Practical PICmicro® Microcontroller Oscillator Analysis and Design AN823 — Analog Design in a Digital World Using Mixed Signal Controllers AN595 — Improving the Susceptibility of an Application to ESD AN688 — Layout Tips for 12-Bit A/D Converter Application

Visit the EMC Design Center at

www.microchip.com/EMC

Need Technical Support TODAY?If you need quick answers to your technical questions, then please contact our 24/7 Technical Support site at: http://support.microchip.com. In addition, Microchip is hiring even more field applications resources in your area, who can work with you on your individual needs. Contact your local Microchip sales office for more details.