Introduction To Microcontrollers
Presenter: Robert V. White

Abstract

Microcontrollers and other programmable digital devices are becoming common in power supply design. Although not often used for the real time PWM loop, they are very useful for housekeeping, protection, data logging and communication. In server power supplies, using a microcontroller for functions like startup sequencing, over temperature protection, and fan speed control can save 100 discrete parts. Aside from the material cost, this is a significant savings in manufacturing cost and a significant reduction in the calculated failure rate.

For many power supply engineers, the world of microcontrollers is a total unknown. Just finding the starting point can be difficult. Trying to talk with an embedded controller engineer can often seem like speaking another language. The jargon and terminology of microcontroller development is overwhelming to the uninitiated.

This seminar provides an introduction - a roadmap and translation guide to the world of microcontrollers and programmable devices. The overall goal is provide the attendee with the basic knowledge of the tools and processes needed for developing microcontroller-based circuits and systems.

Details of Content

The first part of the seminar acquaints the attendee with the various types of devices and their principal characteristics. Microcontrollers, microprocessors, digital signal processors (DSPs), digital signal controllers (DSCs), programmable logic devices (PLDs), and field programmable gate arrays (FPGAs) will be compared and contrasted. Some of the more popular microcontroller families such as the 8051 and Microchip PIC will be given a closer look. The goal is for the attendee to be able to choose the appropriate device for their project.

The goal of the second part is to enable the attendee to choose the appropriate software and hardware tools for their project. The discussion starts with a look at programming in assembly language versus programming in C language. From there, the discussion looks at what it takes to write, test, and debug the code and to move the code into the microcontroller. This includes an introduction to the key programming tools - assemblers, linkers, compilers, Make programs, and integrated development environments (IDEs). Once the program is written, it must be debugged. Tools like simulators, debuggers, and emulators will be presented. In addition, the program must be loaded into the microcontroller. Both external and in-circuit programmers will be described.

The third part of the seminar looks at common functional blocks in microcontrollers and how they can be used in power supply design. First, oscillators, without which no microcontroller can work, are reviewed. Next, timers and interrupts are discussed. Then, functions like PWM outputs, A/D and D/A converters, comparators and other linear devices are presented. The last part of this section is a discussion of communication interfaces such as UARTS, I²C, and SPI.

This seminar is introductory in nature and no previous experience with microcontrollers or programming is needed.

NOTE: This seminar is an introduction to microcontrollers in general. This seminar will not go into any depth on the specifics of using a microcontroller in a power supply, such as how to program a soft start procedure.

Outline

Introduction (5 minutes)

• Seminar purpose, description, timing, mechanics
• Overview of seminar

Programmable Devices (20 minutes)

• Introduce, compare and contrast:
• Microcontrollers
• Microprocessors
• Digital Signal Processors (DSPs)
• Digital Signal Controllers (DSCs)
• CPLDs, FPGAs

Popular Devices and Architectures (20 minutes)

• What does "8 bit," "16 bit," "32 bit" mean?
• Introduce, compare and contrast:
• 8051 and derivatives
• Microchip PIC

Languages (15 minutes)

• Advantages and disadvantages
• Assembly language
• C

Development Process (10 minutes)

• Write code
• Build hardware
• Convert software to machine language
• Assemble
• Compile
• Link/Make
• Transfer program into the microcontroller
• Debug

Development Tools (60 minutes)

• Software tools
• Assemblers
• Linkers
• Compilers
• Make
• Simulators
• Integrated Development Environments (IDEs)
• Hardware tools
• Programmers
• Debuggers
• Emulators

Common Peripherals (40 minutes)
Peripherals in this sense means functions in the microcontroller that are not part of the computation core. Example: Timers.

• Oscillators
• Timers
• I/O ports
• PMW outputs
• A/D and D/A
• Comparators and other linear devices
• Communication ports
• Serial/UART
• SPI
• I²C
• Others

Questions and Answers (10 minutes)

Speaker Biography

Bob White

Bob has broad experience in designing power supplies, dc-dc converters and power systems for electronic equipment. He is widely recognized as an expert in power systems architecture and digital power management. Bob is the principal author of the PMBus^TM specifications and continues to chair the PMBus Specification Working Group. He is a well known speaker and author who has presented many papers and seminars at conferences such as the IEEE Applied Power Electronics Conference (IEEE APEC), the European Power Electronics Conference (EPE), the IEEE International Telecommunications Energy Conference (INTELEC), the IEEE International Congress on Power Electronics (CIEP) and the Digital Power Forum. In more than 25 years of professional experience, Bob has worked for Vu1 Corporation, Emerson Network Power/Artesyn Technologies/Zytec Corporation, AT&T Bell Labs/Power Systems, the Digital Equipment Corporation and General Electric.

Bob has a SBEE from MIT (1980) and a MSEE from the Worcester Polytechnic Institute (1991).

He is a Senior Member of the IEEE, in which he has been active for 20 years. He was elected to the Power Electronics Society's executive committee three times, served two terms as the Society's Technical Vice President and represented the Power Electronics Society in the 1990 IEEE Colloquium to South America. Bob is well known for his key role in developing and supporting the IEEE Applied Power Electronics Conference (APEC). He has served on the conference committee in various roles since 1988 and has served twice as the General Chair (1990, 2000). Bob was awarded the IEEE Third Millennium Medal in 2000 and the IEEE Power Electronic Society's Distinguished Service Award in 2002. The Power Sources Manufacturers Association (PSMA) recognized Bob in 2005 for his contributions to and leadership of the PSMA and APEC.