ECE 556 Lab 2 Pre-Lab
Procedure
Part 1
Design a Zener voltage regulator with the following specifications:
35V ≤ Vin ≤ 60V
1.
Input voltage:
2.
Output Voltage: 30 V ≤ Vout ≤ 32 V
3.
Maximum output current: 10 mA
To solve this problem:
1. Create a MathCAD or Maple file that calculates or chooses each component of your circuit (in this case the resistor
and Zener), and calculates the worst-case power dissipated by each component.
2. Run PSpice simulations to show that your circuit works. The simulations should show that when the input varies
between 35 and 60 volts, the output is constant at your chosen design voltage. You need to show this at no load and
at full load.
Part 2
Design an OP-AMP/Pass-Transistor based voltage regulator with the following specifications:
35V ≤ Vin ≤ 60V
1.
Input voltage:
2.
3.
4.
Output Voltage: 25 V
Maximum output current: 2 A
Add a current limiting circuit that starts reducing the output voltage when the output current exceeds 2.5 amps.
To solve this problem:
1. Create a MathCAD or Maple file that calculates or chooses each component of your circuit, and calculates the
worst-case power dissipated by the pass transistor. Use an LM324 for the OP-AMP and a TIP102 for the transistor.
2. Run PSpice simulations to show that your circuit works. The simulations should show that when the input varies
between 35 and 60 volts, the output is constant at 25 V. You need to show this at no load and at full load.
3. Run a PSpice parametric sweep to sweep the load current from 1 uA to 4 A and generate a plot of output voltage
versus load resistance (or load current). This simulation will show that the output of your regulator is constant with
output current until it reaches the current limit. At the current limit, the voltage should drop off.