Microprocessor PCB Design

1
Microprocessor PCB Design

• by
• Tuan Hung Huynh
• April 3, 2006

2
Outline

• Background
• Design Process
• Application
• Results

3
Purpose

• Designing computer circuits and software for the
  Microprocessor class.
• PCB layout software
• Documentation

4
Background
5
Past Designs

• People to mention
• Wi Sugiri (projects)
• Dan Sossaman (board)
• Neil Clukode
• Matt Olson
• Tuan Huynh
• Chris Carpenter

6
Microcontroller

• Microcontroller or Microprocessor?
• Microcontroller basic
• Microprocessor - complex
• Atmel and Intel 8051 core architecture
• AT89S8252 (8052)
• AT89S8253 (8053)

7
Design Process
8
Structure

• Developing the schematic layout
• Updating and improvements
• Ordering of components
• Developing software
• Transforming into a workable circuit
• Testing and demonstration
• Optional manufacture of the PCB

9
Protel

• Schematic Layout

10
Protel

• Schematic and PCB Libraries
• Custom components
• Link of files

PCB library
Schematic library
11
Protel

• PCB Layout
• Physical representation

12
Protel

• Design Rule Check (DRC)
• Short Circuits
• Broken Nets
• Height and Width Constraints
• Hole Size
• Clearance Constraints

13
Protel

• Assembly Files
• Gerber Files
• NC Drill Files

.GTL Top Layer
.GBL Bottom Layer
.GTO Top Overlay
.GBO Bottom Overlay
.GTS Top Soldermask
.GBS Bottom Soldermask
.GKO Keep-out Layer
.apr Drill Files
.drr Drill Files
.drl Drill Files
14
Assembly Files

• Top Silkscreen

15
Assembly Files

• Top and Bottom Copper

16
Assembly Files

• Top Soldermask and Bottom Soldermask

17
Assembly Files

• Drill File

18
Creation of the PCB

• Board Manufacture
• Advanced Circuits
• www.4PCB.com
• www.FreeDFM.com
• Component Vendors
• Digikey
• All Electronics

19
Application
20
Microprocessor Projects

• Microprocessor Design class
• Digital Metronome
• T-Bird Taillights
• Digital Clock
• Serial Communication
• Memory Mapped Input/Output
• 7-Segment Displays
• Keypad Input
• LCD Display

21
Microprocessor Projects

• Digital Metronome
• T-Bird Taillights
• Digital Clock
• Port 3

22
Microprocessor Projects

• Serial Communications
• Hyper-terminal
• RS232 buffer chip
• Serial cable

23
Microprocessor Projects

• Serial Communications Cable
• DB9 to RJ45

24
Microprocessor Projects

• Memory Mapped Input/Output
• Data latch

25
Microprocessor Projects

• 7-Segement Displays
• Data latch
• Programmable logic device
• FETs

26
Microprocessor Projects

• Keypad
• Data latch
• PLD

27
Microprocessor Projects

• Liquid Crystal Display
• Data latch
• PLD

28
Problems Encountered

• Issues with new microcontrollers
• Chip burners
• Capacitance
• Internal Fuse Bits
• In-System-Programming Circuit

29
In-System-Programming

• Modification of the board is possible
• Buffer chip
• Programmable logic device
• Re-wire

30
In-System-Programming

• ISP Cable
• DB25 to RJ45

31
Results
32
Completion

• Board applied in the classroom
• Update from previous designs
• Capable of future updates

33
Future Design

• Reduction of Components
• Dual Microcontrollers
• USB
• Surface Mount Components

34
Questions
35
References

• Marcus O. Durham, PhD. Systems Design and the
  8051. Second Edition. TechnoPress. Tulsa, OK.
  2003 2004.
• Altium Protel
• http//www.4pcb.com
• http//www.allelectronics.com
• http//www.play-hookey.com/digital/experiments
• /seven_seg_led.html