NO NO'S IN DESIGN
DO NOT DO OR USE THE FOLLOWING
TYPES OF ACTIONS:THESE ARE
UNACCEPTABLE AND WILL RESULT IN
DOING IT OVER :
LET US USE
ONE GUESSES THAT
LET US APPROXIMATE
WE ASSUME
THE RULE OF THUMB IS
ACCEPTABLE DESIGN RULES
CALCULATIONS BASED ON
ACCEPTED SCIENTIFIC FACT
AND RULES GOVERNING THE
BASIC DESIGN PROCEDURE
-- EVERY VALUE SHOULD BE
JUSTIFIED AND CALCULABLE
FUNCTIONAL REQUIREMENT OR SPECIFICATIONS
OVERALL SPECIFICATIONS
DOES NOT NECESSARILY REFLECT THE
EXACT DETAILS OF THE ACTUAL CIRCUIT
MAY HAVE TO BE CHANGED IF THE DESIGN
SPECIFICATIONS OF A REAL CIRCUIT DO NOT
ALLOW THE FUNCTIONAL SPECS TO BE MET
MAY HAVE TO MEET WORLD, NATIONAL, STATE,
COUNTY, CITY, COMPANY, RECOGNIZED
STANDARD
DESIGN SPECIFICATIONS
PROVIDE DEFINITION OF WHAT IS TO BE DESIGNED
TELL ENGINEER WHEN A DESIGN IS COMPLETED -DESIGN DONE WHEN SPECS ARE MET
THERE ARE INIFINITE NUMBER OF POSSIBLE DESIGNS
NO ONE RIGHT WAY
GENERALLY, ENGR HAS ALMOST COMPLETE FREEDOM
TO SELECT THE CIRCUITS AND PARAMETERS
EXAMPLES OF BADNESS
CALCULATION OF LOAD RESISTOR
USE ONE TENTH (1/10TH)THE LOAD SIZE SO
CIRCUIT WILL NOT AFFECT THE LOAD
CALCULATION OF RE EMITTER RESISTOR
PUT ONE THIRD (1/3 RD) OF VCC ACROSS RE
DESIGN STEPS EXAMPLE
AMPLIFIER
•
•
•
•
•
•
NUMBER OF STAGES?
TYPES OF DEVICES?
GAIN BANDWIDTH PRODUCT?
FT OR HIGH FREQUENCY CUTOFF
FREQUENCY OR UNITY GAIN
FREQUENCY
CALCULATE THE FT NEEDED PER
STAGE
FREQUENCY CALCULATIONS
• IF DOWN TO DC -- EASY NO
CALCULATIONS NECESSARY
• IF SOME LOW FREQUENCY -- THEN
SIMILAR TO HIGH FREQUENCY
CALCULATIONS
• HOW DO WE MAKE THIS
CALCULATION?
DESIGN FORMAT FOR EE CLASSES
1. Statement of design philosophy
A. Approach
B. Justification
2. Block diagram or schematic as applicable (Computer Generated)
3. Hand Calculations to fill 2. above.
4. Final Schematic with all values. (Not hand drawn)
5. Spice or other computer program
A. Netlist
B. Output diagrams
1. Frequency Response
2. Phase Response
3. Noise
4. Any other diagrams or charts to show compliance
6. Use only EIA parts.
7. All work will be individually done, any cheating will be greeted with a F in the
course.
8. Each report will have the following :
A. Title Page with:
1. Design Problem Number and title
2. Your Name and ID NO
3. Phone number and email
B. Table of Contents
1. Design Philosophy
2. Hand Calculations
3. Computer Calculations
4. Computer printouts
9. All reports except for the hand calculations are to be typewritten or
wordprocessed.
Each report is to be written in third person not personal.