in this issue looking for an inexpensive way to increase...

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

INTHISISSUEPAGE 1

Microchip’s newest 20-pin PIC® microcontrollers

PAGE 2

New 16-bit devices for complete digital loop control

PAGE 3

Weigh Scale Applications for the MCP3551

PAGE 4

Bit Bashing: How to generate another PWM when you need just one more

PAGE 5

Predicting the Failure of Your Fan Brings Many Advantages

PAGE 6

Intelligent Battery Charger Reference Design

PAGE 7

Production Programming Service through microchipDIRECT

PAGE 8

How Managers Become Barriers

PAGE 9

Using a PIC® Microcontroller as a Clock Source for a SMPS PWM Generator

PAGE 10-11

WebSeminars

PAGE 12

What’s new in Microchip literature?

PAGE 13

Web Site Highlights

Microchip is hiring!

INTHISISSUE

Microchip’s newest 20-pin PIC® microcontrollers offer a cost-effective entry point for designers looking to migrate from 14-pin devices to those with more memory, functionality and I/O.With the introduction of the PIC16F631 and PIC16F677, Microchip now offers the market’s lowest-cost Flash microcontroller with hardware I2C™ capability (PIC16F677) and our least expensive 20-pin mid-range device (PIC16F631) to date. The devices feature up to 3.5 KB of Flash, 256 Bytes of data EEPROM, 128 Bytes of SRAM, and 12 ADC channels (PIC17F677 only) — giving you the option to easily add new functionality to systems utilizing 14-pin PIC microcontrollers or reduce system cost on existing 20-pin designs.

The devices are a code and pin-compatible extension of the PIC16F690/689/687/685 family and offer many advanced features, including:

• A software-selectable 8 MHz internal oscillator• A 31 kHz low-power oscillator with seamless, on-the-fly clock switching• In-Circuit Serial Programming™ (I2C™)• Brown-out Reset with software control option• Synchronous Serial Port (SSP) with I2C address mask option (PIC16F677

only)• Advanced analog comparator module – 2 comparators – Set/Reset Latch mode – 0.6V reference for comparators and

ADC• Ultra low-power wake-up• Enhanced low-current Watchdog Timer• Low-power Timer 1 oscillator• Up to 18 I/O pins• 4mm x 4mm QFN package option

for extremely space-constrained applications

Looking for an inexpensive way to increase the capability of your 8- or 14-pin design?

The PIC16F631 and PIC16F677 are available today for general sampling and volume production in RoHS-compliant 20-pin PDIP, SOIC, SSOP and QFN packages. A full suite of tools is available for the pair, including the MPLAB® IDE Integrated Development Environment, MPLAB ICD 2 In-Circuit Debugger, MPLAB ICE 2000 In-Circuit Emulator, MPLAB ICE 4000 In-Circuit Emulator, PRO MATE® II Universal Device. Programmer, MPLAB PM3 Universal Device Programmer and the PICkit™ 2 Starter Development Kit.

Formoreinformationvisitwww.microchip.com/StartNow.

Download the PIC16F631/677/685/687/689/690 Data Sheet

today!

http://techtrain.microchip.com/PICKit2Sem/

http://ww1.microchip.com/downloads/en/DeviceDoc/41262B.pdf

MICROCHIPTECHNOLOGY’SmicroSOLUTIONSeNEWSLETTER-July2006

www.microchip.com Microcontrollers•DigitalSignalControllers•Analog•SerialEEPROMs 2

RETURNTOFRONTPAGE

Check out Microchip’s new 16-bit devices if your design includes AC/DC converters, isolated DC/DC power converters and other power-conversion applications, such as embedded power-supply controllers, power inverters and Uninterruptible Power Supplies (UPSs). The new dsPIC30F1010, dsPIC30F2020 anddsPIC30F2023 (dsPIC30F202X) Digital Signal Controllers (DSCs) are ideal for common, multi-loop Switch Mode Power Supplies (SMPSs) and other power-conversion applications.

While Microchip’s microcontrollers have long been used in intelligent power supplies for communications, power-sequencing, soft-start and topology control, lack of effective solutions has hampered the development of supplies using digital control of the complete power-conversion loop. The dsPIC30F1010 and dsPIC30F202X DSCs allow you to implement this type of complete digital control of your products.

The SMPS dsPIC® DSC families were developed with input from leading power-supply manufacturers to tip the scale in favor of a digital approach. These devices accelerate innovation by giving you the flexibility to create new topologies that were formerly impractical for analog approaches. Early adopters expect to achieve superior levels of customization, resulting in power supplies that are more competitive in their markets.

The new DSCs enable full control of the power- c o n v e r s i o n p r o c e s s

via software running on the DSC and through its high-performance integrated peripherals. You are no longer limited by analog-control design techniques. Components no longer need to be “oversized” to account for component variation. There is no need to worry about component drift and temperature compensation. Manual tuning at the end of the manufacturing line is now a thing of the past. Fewer product platforms are required to serve a wider range of applications, as they are differentiated through software, rather than hardware. Additionally, new digital topologies provide you with a higher degree of freedom to

Looking for complete digital control of a power-conversion feedback loop?develop supplies with improved power density and improved cost effectiveness.

Applications that can immediately see cost and performance benefits from Microchip’s SMPS solution include power supplies with multiple outputs, coordinated load sharing, hot-swap capability, output coordination, integrated power factor correction or extensive fault handling. A host of other applications can benefit from the ultra-fast PWM and A/D onboard the dsPIC30F1010 and dsPIC30F202X devices, such as digital lighting and Liquid Crystal Display (LCD) backlights.

The PWM on-board these devices offers 1 ns duty cycle resolution and seven modes of operation, including standard, complementary, push-pull and variable-phase. The 10-bit A/D converter has up to 12 input channels and samples at up to 2 MSPS. Advanced

sampling capabilities include individual triggers for each of four sample and holds, and precise, uniquely-timed or simultaneous sampling.

The dsPIC30F1010 devices have 6 Kbytes of Flash and two PWM generators, and the dsPIC30F202X devices have 12 Kbytes of Flash and four PWM generators. All devices in this family operate between 3.0 and 5.5 volts. Additional features include:

• Onboard high-speed analog comparators (2 or 4)• 30 MIPS performance at 5.0 volts• Small footprint QFN package (6 mm x 6 mm)• Fast, deterministic response• Extended temperature operation (-40°C to 125°C)• Optional PWM dither mode for Electromagnetic Interference (EMI) reduction

The SMPS DSCs are suppor ted by the MPLAB® IDE Integrated Development Environment, MPLAB C30 C Compiler, MPLAB SIM 30 Software Simulator, MPLAB ICD 2 In-Circuit Debugger and MPLAB Visual Device Initializer. Additionally, Microchip offers the dsPICDEM™ SMPS Buck Development Board (Part # DM300023), which is available for early adopter sampling today. Microchip anticipates receiving orders for it at www.microchipdirect.com in September.

“Power supplies with higher power or complexity are now poised at a price threshold that is amenable to digital control,” — Sumit Mitra, vice president of Microchip’s Digital Signal Controller Division

FormoreinformationvisittheSMPSApplicationDesignCenteratwww.microchip.com/Power.



RETURNTOFRONTPAGE

AN1030 - Weigh Scale Applications for the MCP3551Written by: Jerry Horn, Gordon Gleason, Lynium, L.L.C

There are many different types of sensors whose underlying realization is based on a Wheatstone bridge. Strain gauges are one such sensor. As a material is strained, there is a corresponding change in resistance. In many cases, each side of the Wheatstone bridge may respond to the strain by lowering or increasing in resistance.

This application note focuses specifically on load cells, a type of strain gauge that is typically used for measuring weight. Even more specifically, the focus is on fully active, temperature-compensated load cells whose change in differential output voltage with a rated load is 2 mV to 4 mV per volt of excitation (the excitation voltage being the difference between the +Input and the –Input terminals of the load cell).

The goal is to develop a variety of circuits that can quantify this change via an analog-to-digital converter (ADC), which is a MCP3551, 22-bit Delta-Sigma ADC. The analysis for each circuit should be applicable to other resistive bridge sensors. The different circuits allow cost versus performance trade-offs.

The circuits presented in this application note have been realized in the MCP355X Sensor Application Developer’s Board whose block diagram. This board includes two microcontrollers. The PIC16F877 performs the basic weigh scale function

while the PIC18F4550 sends data to a Personal Computer (PC) for analysis and debugging. The board includes a display, as well as input switches that are used for calibrating the zero point and full-scale point of the load cell and for setting various processing options. Conversion results from the currently selected ADC are communicated to the PC over the USB bus. This data can be viewed on a PC using the DataView™ software that comes with the reference design. All of the testing and results shown in this application note were done with an MCP355XSensorApplicationDeveloper’sBoard, DataView software and various load cells and/or load cell simulators that are either described in this document or can be easily purchased.

The MCP3551 is an ideal ADC for a variety of resistive bridge applications. It can be connected directly to the sensor or it can be used along with other components to provide increased resolution and precision. With the addition of a PIC® microcontroller and a couple of switches, less expensive operational amplifiers can be used while still achieving excellent results.

This application note looks at three different circuits for use with load cells, a type of resistive bridge sensor. Collectively, the circuits provide performance ranging from 10 bits of “noise-free” resolution up to 16 bits. This resolution is available for a sensor whose differential output voltage ranges from 0V to 10 mV. For a sensor with a larger output voltage range, even higher resolution can be achieved.

MCP355X Sensor Application Developer’s Board whose block diagram

Todownloadthecompleteapplicationnote,visithttp://ww1.microchip.com/downloads/en/AppNotes/01030a.pdf

MCP355XSensorApplicationDeveloper’sBoardPartNumber: MCP3551DV-MS1DevicesSupported: MCP3551, MCP3553, MCP3550-50, MCP3550-60

The MCP355X Sensor Developer’s Board allows for easy system design of high resolution systems, such as weigh scale, temperature sensing or other small signal systems requiring precise signal conditioning circuits. The reference design includes LCD display firmware that performs all the necessary functions, including ADC sampling, USB communication for PC data analysis, LCD display output, zero cancellation, full-scale calibration and units displayed in gram (g), kilogram (kg) or ADC output units.

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1335&dDocName=en024597







RETURNTOFRONTPAGE

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: One PWM, two PWM, three PWM, four —

How to generate another PWMwhen you need just one more.

Written by: Keith Curtis, Principal Applications Engineer

The focus this month is motor control, or more specifically, controlling more than one motor. For an evening event at our annual MASTERs conference, it was necessary to generate two related PWM outputs. However, because we wanted to highlight our new 14-pin microcontroller with PWM, the PIC16F616, we had a problem, because there is only one available on the chip. So, how do you generate two PWM signals with only one CCP module?

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

The answer is in a technique called ‘pulse swallowing’. The same PWM pulse is used to drive both motor drivers. Evenly spaced PWM pulses are ‘swallowed’ (shorted out) on the motor drive that is running at the slower rate. See Figure 1 for an example pulse chain and Figure 2 for an example circuit.

In the example, Motor B is initially loosing every other pulse. This is caused by RC3 being made to output a LOW during the pulse to be swallowed. When the pulse is to be passed to Motor B, RC3 is tri-stated and the pulse passes through to the MOSGET driver, then to the output. Because of the inertial of the motor acts like a low-pass filter, the missing pulses are mechanically averaged with the pulses that are present, effectively reducing the average duty cycle for the motor. In this example, the duty cycle of Motor A is effectively twice that of Motor B.

So, how do we short out specific pulses from the PWM? We start with the Timer2 interrupt, which fires at the start of every pulse generated by the CCP. In the interrupt service routine, a determination is made as to whether the pulse should be ‘swallowed’, or not, and the output is either driven low or tri-stated. Unfortunately, the latency time of the interrupt function, and the variable nature of the determination function, make it impossible to accurately shutdown a pulse before it starts. So, the interrupt service routine uses a flag which passes from one interrupt to the next. If the flag is set, then the interrupt service routine shorts out the next pulse, if not, then the pulse is allowed to occur.By shorting out the pulse using data from the last interrupt to start the ‘swallow’, and then making the determination for the next interrupt, the latency time is minimized, and more importantly, kept

VDD

VDD

VSS

VBAT

VBAT

VBAT

Figure 2

Figure 3

Continued on next page...



RETURNTOFRONTPAGE

Bit Bashing continued from previous page...

consistent.

Unfortunately, even with the interrupt to interrupt flag, some portion of the pulse will still be generated before the interrupt service routine can ‘swallow’ it. Fortunately, any portion of the pulse that is accidentally generated is subtracted from the next pulse due to the same interrupt delay. See Figure 3

So, We can short out evenly spaced pulses and reduce the average duty cycle, but how do we determine which pulses should be swallowed? Simple, We add an offset to an Accumulator register at each interrupt. When the Accumulator register overflows, we swallow the pulse in the following interrupt. If the offset value is large, then the Accumulator register overflows more often, resulting in a greater number of pulses swallowed. If the offset is small, then it takes longer for the accumulator to overflow and pulses are swallowed less often. Listing 1 shows a pseudo code example of how this is implemented.

Accumulator = Accumulator + Offset

If (Accumulator > Period) /* an over flow condition*/

Swallow_pulse_flag = true

Accumulator = Accumulator – period

Else /* no over flow condition*/

Swallow_pulse_flag = false

Endif

Listing 1

All that remains is to determine the value used in offset. That is calculated using the following equation;

Offset = Full_duty_cycle – Slow_duty_cycle

So, if the period is 200 cycles (0-199 counts) and the full duty cycle is 50 (0-49), with a slow duty cycle if 45 (0-44), the offset is 5 counts. If 5 counts are added to the accumulator at every pulse, the accumulator overflows on every 40 pulses. Out of every 200 pulses, 5 evenly spaced pulses are missing on the slower motor PWM. And there we have it, two PWM channels with one CCP.

FormoreinformationvisittheMotorControlApplicationDesignCenteratwww.microchip.com/Motor

Listen To What Your Fan Is Telling You

DownloadtheFanControlFunctionPackDesignGuideathttp://ww1.microchip.com/downloads/en/DeviceDoc/21835c_.pdf

PredictingtheFailureofYourFanBringsManyAdvantagesAs a fan wears out, it slows down and circulates less air. This can eventually cause an overheating condition and possibly an unexpected thermal shutdown. The TC670 predictive fan failure device monitors the speed of a fan and allows you to set a fan speed threshold at which you receive a fan warning indication, allowing service action to take place on your schedule instead of the fan’s.

The TC670 Fan Failure Detector features:

• Fan wear-out detection for 2-wire linear-controlled fans

• Replacement system for 3-wire fans

• Fan-alert signal when fan speed is below programmed threshold

• Clear capability for eliminating false alarm

• Low operating current, 90 μA (typ.)

• VDD range: 3.0V to 5.5V

• Available in a 6-pin SOT-23 package

TC670 Applications:

• Protection for linear-controlled fans

• Power supplies

• Industrial equipment

• PCs and notebooks

• Data storage

• Data communications equipment

• Instrumentation

Product Specifications

Device VDD RangeTemperature

RangeMaximum IQ

Typical Accuracy

Package

TC670 +3.0V to +5.5V -40°C to +85°C 150 µa ±5% 6 SOT-23



RETURNTOFRONTPAGE

Intelligent Battery Charger Reference DesignTypically, simple battery chargers do not provide the intelligence to charge different battery technologies or batteries with the same technology but different voltages and capacities. At best, this may leave the battery improperly charged. At worst, it can pose a serious safety hazard. A microcontroller can provide the intelligence to overcome these problems.

In addition to intelligent control, the microcontroller can provide a low-cost, flexible solution for charging batteries. Complete battery charging applications may be developed quickly using a microcontroller. Add to this the serial communication capability of the microcontroller, real-time data logging and monitoring is possible. Simple battery chargers use all analog components to accomplish their function. However, by using a microcontroller, a battery charger can be made intelligent.

Microcontroller Benefits

• Flexibility to handle different technologies, voltages and capacities

• Variable voltage generation control

• Charge/Discharge multiple battery packs

• “Windowed” A/D for high resolution

Microchip Technology’s PICREF-2 Intelligent Battery Charger (IBC) Reference Design offers a ready-made battery charger solution. This Reference Design is targeted to battery charger applications, such as camcorders, portable audio equipment, portable phones and portable power tools. With the PICREF-2 Reference Design, you can simply pick a complete battery charging system by completing these steps:

1. Pick the required battery-management features from the modular source code provided.

2. Pick the critical battery pack parameters and modify the global constants to those specifications.

The hardware design contains the necessary circuitry to support charging and discharging algorithms, charge termination methods and RS-232 communications. The modular source code is written in C and consists of the charge termination algorithms, discharge algorithm, inter-device communications and RS-232 communication modules. The PC-based software provides a means for requesting and displaying battery status information.

PICREF-2 Key Features

• Compatibility Across Battery Technologies

• Flexible Development Environment

• Fast Charge Rate

• High Charge Current Capability

• High Discharge Current Capability for Conditioning

• Real-Time Debug

• Data Logging

• User-selectable Embedded Charge Termination Algorithms

Todownloadthecompletereferencedesign,visithttp://ww1.microchip.com/downloads/en/AppNotes/30451c.pdf

http://ww1.microchip.com/downloads/en/AppNotes/30451c.pdf





RETURNTOFRONTPAGE

Need 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 PIC® microcontrollers through 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.

Coming soon to the Production Programming Service are new

features for custom labeling and ink-dot capabilities!

Benefits of Production Programming through microchipDIRECT:• Seamlesslyintegrated

intoyourmicrochipDIRECTaccount

• Codeverificationservicepriortoproduction

• One-stoppoint-of-purchaseforproductandproductionprogramming

• Cost-effective

• Nounitminimumorderrequirements

• Quick-turnfulfillment(programmedorderstypicallyshipwithin48hours)

• AvailabletoallcustomersthroughmicrochipDIRECT

microchipDIRECT

www.microchipdirect.com

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

To meet the stringent design requirements placed on our customers, the following innovative programming options are offered:

FLASH (ELECTRICALLY REPROGRAMMABLE): Flash PIC microcontrollers allow erasing and reprogramming of the program memory in the microcontroller. Reprogrammability offers a highly flexible solution to today’s ever-changing market demands and can substantially reduce time-to-market. You can program your systems late in the manufacturing process or update systems in the field. This allows easy code revisions, system parameterization or customer-specific options with no scrappage. Reprogrammability also reduces the design verification cycle.

ONE-TIME PROGRAMMABLE (OTP): OTP PIC microcontrollers are manufactured in high volumes without customer-specific software and can be shipped immediately for custom programming. This is useful if you need rapid time-to-market and flexibility for frequent software updates.

IN-CIRCUIT SERIAL PROGRAMMING™ (ICSP™): Microchip’s Flash and OTP PIC microcontrollers feature ICSP capability, which allows the microcontroller to be programmed after being placed in a circuit board, offering tremendous flexibility, reduced development time, increased manufacturing efficiency and improved time-to-market. This popular technology enables reduced cost of field upgrades, system calibration during manufacturing and the addition of unique identification codes to the system. Requiring only two I/O pins for most devices, Microchip offers the most non-intrusive programming methodology in the industry.

SELF-PROGRAMMING:Microchip’s PIC16F87X family features self-programming capability. Self-programming enables remote upgrades to the Flash program memory and the end equipment through a variety of medium ranging from Internet and modem to RF and infrared. To setup for self-programming, the designer programs a simple boot loader algorithm in a code-protected area of the Flash program memory. Through the selected medium, a secure command allows entry into the PIC16F87X microcontroller through the USART, I²C™ or SPI serial communication ports. The boot loader is then enabled to reprogram the PIC16F87X Flash program memory with data received over the desired medium. Self-programming is accomplished without the need for external components and without limitations on the PIC16F87X’s operating speed or voltage.

QUICK-TURN PROGRAMMING (QTP): Microchip offers a QTP programming service for factory production orders. This service is ideal for customers who choose not to program a medium-to-high unit volume in their own factories, and whose production code patterns have stabilized.

SERIALIZEDQUICK-TURNPROGRAMMING(SQTPSM):SQTP is a unique, flexible programming option that allows Microchip to program serialized, random or pseudo-random numbers into each device. Serial programming allows each device to have a unique number that can serve as an entry-code, password or identification number.

MASKEDROM: Microchip offers Masked ROM versions of many of its most popular PIC microcontrollers, giving customers the lowest cost option for high-volume products with stable firmware.

http://www.microchipdirect.com/

http://www.microchip.com/Programming



RETURNTOFRONTPAGE

What is the Aggregate System?

The Aggregate System is a comprehensive system for building an 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 the book “Driving Excellence”, Chapter 8, I described various management styles that obstruct the establishment of a values-based, highly empowered, continuous improvement culture. Each of these management styles negatively affects employee empowerment, which fuels continuous improvement. To varying degrees, most managers incorporate a portion of each of these styles within their management style. The trouble arises when any specific style becomes so pervasive that it produces undesirable results. This article discusses two management styles. Please visit www.DrivisngExcellence.biz to order your copy of the book and learn about all 11 management styles that can become barriers.

The “I Need to Review Everything and Participate in All Decisions” Manager

Description

This management style represents the classic “micro-manager” who creates an inefficient bureaucracy by becoming the bottleneck to the organization’s improvement objectives. This is the over-controlling manager who meticulously tracks projects, is in the loop on all decisions and has to put his or her “stamp” on everything. Since practically every proposal, strategy and decision must go through this manager’s office, the manager becomes a barrier to the group’s productivity and rate of improvement.

Advice

If this typifies your management style, you can benefit from resisting the temptation to be involved in everything. First, set the goal to systematically

reduce what you are currently reviewing. Determine the critical points or conditions under which you still need to intervene. Then inform your employees of the new approach. Ensure that you clearly outline your expectations of the employees concerning their newly gained empowerment. Then step back and see the benefits of increased employee empowerment. Continue allowing greater empowerment, coupled with just the right amount of coaching. Instead of having employees do something because you asked them, make projects their responsibility and help them (but remember, not too much).

Tell the employees why you are adopting this new style. Ask for their help by having them let you know when they feel you’re micro-managing. It’s only natural that employees may fear providing you with this type of feedback. Therefore, pay attention to your verbal and non-verbal communication when receiving the feedback. When the employees finally get the guts to tell you that you are micro-managing again, let them know that you have heard and appreciate their feedback. Overcoming this style of management requires that you resist your personality trait or need to be in control. Remember, if you want to be an outstanding manager,

it’s not about you and your needs; it’s about the employees and their needs.

The “Answer” Manager

Description

This represents the manager who is always ready to provide the “answer” to everyone’s issue. Such managers think that since they are in charge, it’s their job to give everyone the solution to the issue at hand. Moreover, since they used to do that job, they know what is best. This manager could have been named the “I’m right” or the “My way is the best way” manager. This style of management is frequently associated with individuals who are not good listeners. The main problem with this style is that it stops employee involvement, creativity and

How Managers Become Barriers

Continued on next page...

http://www.DrivingExcellence.biz



RETURNTOFRONTPAGE

growth. Employees never feel empowered because the answer is always provided. Moreover, few of us learn by being told something. We require the experience of trial and error for something to truly sink in.

Advice

If being the answer manager is characteristic of your management style, and you would like to bring your style more in balance, you should first control the temptation to provide the answer — then, practice trying to be more of a coach. Convince yourself that what you should take pride in is not your own contributions, but those of your employees. It is often easier and more enjoyable to give the answer as you see it to employees, rather than coaching them as they discover the solution. Inherently, there’s nothing wrong with providing solutions for your employees. However, if you want to build and maintain a strong, competent, committed and enthusiastic team, you need to put the gratification of fulfilling some of your needs on the back burner. For example, you may feel good when you come up with the answer to someone’s issue. It may give you a sense of importance, prestige, job security or just challenge. However, a manager’s true job is to build and maintain a team that achieves excellence. So, keep the focus on making every employee a stronger and more robust performer.

You must learn to facilitate the employees in their discovery to uncover the answer. The best technique for accomplishing this is to keep asking questions (sometimes leading questions) that lead them to the solution. “Have you thought about this?” “How are you going to deal with this or that item?” “Who do you think you need to talk to?” Use questions to “fill in the

gaps” where the employee has fallen short. “Do you think that maybe you should talk to John about this?”

You can tell that this approach is working when employees frequently come to you on their own to discuss what they’re thinking or planning. They’re doing this because it adds value, not because you have the answer.

— Steve Sanghi, President and CEO of Microchip Technology Inc.

Continued from previous page...

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

Using a PIC® Microcontroller as a Clock Source for a SMPS PWM Generator

A PIC microcontroller can be used as the clock source for a PWM generator, such as the MCP1630.

The MCP1630 begins its cycle when its clock/oscillator source transitions from high-to-low, causing its PWM output to go high state. The PWM pulse can be terminated in any of three ways:

1. The sensed current in the magnetic device reaches 1/3 of the error amplifier output.

2. The voltage at the Feedback (FB) pin is higher than the reference voltage (VREF).

3. The clock/oscillator source transitions from low-to-high.

The switching frequency of the MCP1630 can be adjusted by changing the frequency of the clock source. The maximum on-timer of the MCP1630 PWM can be adjusted by changing the duty cycle of the clock source.

The PIC microcontroller has several options for providing this clock source:

• The FOSC/4 pin can be enabled. This produces a a 50% duty cycle square wave that is 1/4th of the oscillator frequency.

• For PIC microcontrollers equipped with a Capture/Compare/PWM (CCP) or Enhanced CCP (ECCP) module, a variable frequency, variable duty cycle signal can be created with little software overhead. This PWM signal is entirely under software control and allows advanced features, such as soft-start, to be implemented using software. For smaller parts that do not have a CCP or ECCP module, a software PWM can be created.

FormoreinformationdownloadtheIntelligentPowerSupplyDesignTips‘nTricksBookletat

http://ww1.microchip.com/downloads/en/DeviceDoc/41283A.pdf

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1335&dDocName=en025844&link=Banner



RETURNTOFRONTPAGE

Register Now!

FormoreinformationaboutLiveWebSeminarsorArchivedWebSeminarsvisit:www.microchip.com/webseminars

Category WebSeminarTitle

Analog

Signal Chain Overview

Do I Filter Before, After or Never?

Designing Intelligent Power Supplies

Thermistor Application for the New MCP6S9X PGA

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

Select the Right Operational Amplifier for Your Filtering Circuits

Amplify Sensor Signals using the PGA

Connectivity

Microchip’s ENC28J60 Smallest Ethernet Controller

Serial Communications using the dsPIC30F I²C™ Module

Serial Communications using the dsPIC30F CAN Module

dsPIC® DSC SPI Communication Module

dsPIC® DSC UART Module

Emulating RS-232 Over USB Using the PIC18F4550

An Introduction to Controller Area Network (CAN)

Wireless Communication using the IrDA® Standard Protocol

Design Considerations When Adding CANbus to Your System

DevelopmentTools

Choosing a Debug Tool

Introduction to the Signal Analysis PICtail™ Daughter Board

Basic dsPIC® DSC Development Tools

Introduction to MPLAB® SIM Software Simulator

Tips and Tricks Using MPLAB® v6.61

Introduction to the MPLAB® Visual Device Initializer (VDI)

Introduction to MPLAB® IDE

Introduction to Microchip’s Development Tools


Memory Serial EEPROM Overview

MotorControl

dsPIC30F Motor Control PWM Module

Introduction to Mechatronics and the Mechatronic Design Center

AC Induction Motor (ACIM) Control Using the PIC18FXX31

Brushless DC motor (BLDC) Motor Control Using PIC18FXX31

ThermalManagement

Introduction to the MPLAB® Visual Device Initializer (VDI)

Smaller Packages = Bigger Thermal Challenges

PowerManagement


Developing Intelligent Power Systems using the MCP1630 High-Speed PWM

Lithium-Ion Battery Charging: Techniques and Trade-offs

SystemDesign

Do I Filter Before, After or Never?


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

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

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

Techniques that Reduce System Noise in ADC Circuits

Microchip offers dozens of WebSeminars that are archived as a Windows Media® file. They can be viewed as a streaming file or downloaded to your own computer for viewing whenever you want. You can download the Windows Media® Player for free from www.microsoft.com/windows/windowsmedia/.

A PDF file is also available with the slides that were presented and any speaker notes that are available.

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=84

www.microchip.com/webseminars


http://www.microsoft.com/windows/windowsmedia/player/11/default.aspx



RETURNTOFRONTPAGE

Register Now!


DigitalSignalControl

dsPIC33F DMA Controller

Intro to dsPIC33F Architecture (Part 1)

Intro to dsPIC33F Architecture (Part 2)

dsPIC30F General Purpose Timers

Serial Communications Using the dsPIC30F I²C™ Module

Serial Communications Using the dsPIC30F CAN Module

dsPIC® DSC SPI Communication Module

dsPIC® DSC UART Module

dsPIC30F Quadrature Encoder Interface Module

dsPIC30F Motor Control PWM Module

dsPIC30F 12-bit ADC Module (Part 1)

dsPIC30F 12-bit ADC Module (Part 2)

dsPIC30F Addressing Modes (Part 1)

dsPIC30F Addressing Modes (Part 2)

Introduction to dsPIC30F DSP Engine and ALU

Introduction to dsPIC30F Interrupts

dsPIC30F 10-bit ADC Module (part 1)

dsPIC30F 10-bit ADC Module (part 2)

Introduction to dsPIC30F Architecture (Part 1)

Introduction to dsPIC30F Architecture (Part 2)

Introduction to the dsPIC® DSC

Basic dsPIC® DSC Development Tools



PIC®MCUs

Introduction to Mechatronics and the Mechatronic Design Center

Emulating RS-232 Pver USB Using the PIC18F4550

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

64 Kbyte Flash MCUs in 28-/40-pin Packages — the PIC18F4620 and PIC18F2620

Introduction to the Signal Analysis PICtail™ Daughter Board


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

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

PIC10F Development Tools: Small Tools for Small Parts

Control the World with the Microchip’s Smallest Microcontroller (PIC10F)

Driving Lumileds LEDs with Microchip Microcontrollers

AC Induction Motor (ACIM) Control Using the PIC18FXX31

Peripheral-rich, Low Pin Count, PIC® MCUs with nanoWatt Technology

Brushless DC (BLDC) Motor Control Using PIC18FXX31

Microchip’s nanoWatt Technology

FormoreinformationaboutLiveWebSeminarsorArchivedWebSeminarsvisit:www.microchip.com/webseminars

Microchip’s WebSeminars allow you to learn more about our products without having to leave the office!

Check out the upcoming live WebSeminars, as well as some of our archived WebSeminars that are available for you to view whenever you want.




http://techtrain.microchip.com/webseminars/Upcoming.aspx

http://techtrain.microchip.com/webseminars/Archived.aspx



RETURNTOFRONTPAGE

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, 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

ProductGuide Product Selector Guide - July to September 2006 DS-00148L2 web/printed

Tips‘nTricks PIC10F200, Intelligent Power Supply Design Tips ‘n Tricks Booklet DS-41283A web/printed

ApplicationNoteAN897, Thermistor Temperature Sensing with MCP6S2X PGA DS-00897C web

AN1030, Weigh Scale Applications for the MCP3551 DS-01030A web

DataSheet

TC4423A/4424A/4425A, 3A High-Speed Power MOSFET Drivers Data Sheet DS-21998A web

TC913A/TC913B, Dual Auto-Zeroed Operational Amplifiers Data Sheet DS-21482C web

PIC12F683 Data Sheet DS-41211C web

PIC18F2423/2523/4423/4523 Data Sheet DS-39755A web

PIC16F631/677/685/687/689/690 Data Sheet DS-41262B web

ErrataPIC18F2420/2520/4420/4520 Rev. A1 Silicon Errata DS-80209E web

PIC18F2455/2550/4455/4550 Rev. A3 Silicon Errata DS-80220E web

ProductBrief MCP1727, 1.5A, Low-Voltage, Low-Quiescent Current LDO Regulator Product Brief DS-21997A web

User’sGuide

MCP6SX2 PGA Thermistor PICtail™ Demo Board User’s Guide DS-51517B web

MCP9800 Thermal Sensor PICtail™ Demo Board User’s Guide DS-51528B web

MCP355X Sensor Application Developer’s Board User’s Guide DS-51609A web

TC72 Digital Temperature Sensor PICtail™ Demo Board User’s Guide DS-51482B web


http://ww1.microchip.com/downloads/en/DeviceDoc/00148L2.pdf

http://ww1.microchip.com/downloads/en/DeviceDoc/41283A.pdf


http://ww1.microchip.com/downloads/en/AppNotes/01030a.pdf

http://ww1.microchip.com/downloads/en/DeviceDoc/21998a.pdf

http://ww1.microchip.com/downloads/en/DeviceDoc/21482c.pdf

http://ww1.microchip.com/downloads/en/DeviceDoc/41211c.pdf


http://ww1.microchip.com/downloads/en/DeviceDoc/41262b.pdf

http://ww1.microchip.com/downloads/en/DeviceDoc/80209e.pdf









RETURNTOFRONTPAGE

websiteHIGHLIGHTSDid you know…It’s easy to discover how small microcontrollers and digital signal controllers are being used in various modules to provide more flexibility and more intelligence. Just visit Microchip’s new Intelligent Power Supply Design Center at

www.microchip.com/power.

IT’STIMETOCONSIDERANEWCAREERAT

MICROCHIPTECHNOLOGYINC.Microchipishiring!Thefollowingpositionsarecurrentlyavailable:ApplicationsEngineer•AssociateEngineer•CADLibraryManager•CorporateApplicationsEngineer•Design

Engineer•DiffusionProductionSupervisor•EmbeddedApplicationsEngineer•EmbeddedSoftwareEngineer

•EngineeringTechnicianII•FailureAnalysisEngineer•FieldApplicationsEngineer•FieldApplicationsManager

•FieldSalesAdministrator•FieldSalesEngineer•HumanResourcesManager•InformationSystemsWintel

DMZInfrastructureArchitect•JuniorPlanner•LayoutDesignerII•LeadLayoutDesigner•LibraryDesign

Engineer•LogisticsCoordinator/Planner•MarketingApplicationsEngineer•microchipDIRECTCustomer

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

Engineer/ProjectLeader•PrincipalArchitect•PrincipalCorporateApplicationsEngineer•PrincipalDesign

Engineer•PrincipalProcessEngineer•PrincipalProductQualityEngineer•PrincipalTestEngineer•Process

Engineer•ProcessTech•ProductMarketingEngineer•ProductMarketingManager•ProductionSpecialist

•PublicationsSpecialist•RegionalDistributionManager•SectionLeader/PrincipalTestEngineer•Senior

ApplicationsEngineer•SeniorCADEngineer•SeniorDesignEngineer•SeniorEngineer,Marketing•Senior

EngineeringTechnician•SeniorEquipmentTech(WetProcess)•SeniorFacilitiesTechnician•SeniorField

SalesEngineer•SeniorInternetEngineerwithE-commerceFocus•SeniorInventoryControlClerk•Senior

LayoutDesigner•SeniorMarketingCommunicationsGeneralist•SeniorOracle/SQLServerManufacturing

DatabaseAdministrator•SeniorProcessEngineeringTechnician•SeniorProductEngineer•SeniorSoftware

Engineer•SeniorTechnicalEditor•SeniorTestEngineer•Senior/PrincipalApplicationsEngineer•Senior/

PrincipalMemoryProductEngineer•Senior/PrincipalMemoryTestEngineer•Senior/PrincipalProbeProcess

Engineer•Senior/PrincipalVerificationEngineer•SeniorSoftwareEngineer•SupplyManagementAnalyst

I•TacticalMarketingManager•TechnicalEditor•TechnicalTrainingEngineer•TestEngineer•Windows®

SystemsAdministrator•YieldEnhancementEngineer

Formoreinformationabouttheseandotherpositions,pleasevisitwww.microchip.com/careersorsendyourresumetoresumes@

microchip.comtoday!

www.microchip.com/careers

FEATURED WEB LINKS:

www.microchip.com/power

www.microchip.com/power























http://www.microchipdirect.com/productsearch.aspx?Keywords=MCP73831T

http://www.microchipdirect.com/LeadPromo.aspx

https://www.microchipdirect.com/programming/default.aspx


http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1335&dDocName=en025844&link=Banner

in this issue looking for an inexpensive way to increase...

Documents