Equipment:
You must make up a complete equipment list and have your instructor review it before you start.
 

Objectives:

• To find the best operating point for a MOSFET amplifier

• To design a CSC amplifier according to a set of specifications

• To design a CDC amplifier with current mirror according to a set of specifications

• To establish the relationship between the voltage gain and the load

 

 
 
 
 
 
 
 
 
 
 
 

Figure # 1

1.- (Lab HW) Design of Common Source

Design a Common Source voltage amplifier using circuit shown in Fig # 1.

Design Specifications

1. VDD = 24 V DC

2.  |AV| > 15 (when loaded with RL= 2 k W )

3.  RIN > 300 KW

4.  Maximum Power Transfer must occur when loaded with RL= 2 k W (Use this info to find  ROUT)

5.  Vin max(before distortion) ³ 60 mVpeak (when loaded with RL=2 k W)

• Show all design calculations.
• Simulate the circuit using ORCAD.
• Compare the ORCAD results to your design calculations and specifications and explain any and all differences.

2.- Assembly, Test and Verification of Specifications

Build and test your design. Measure and verify that your design meets all the given specifications.

   a.Measure VG, VS, VD, and ID with no small signal input.

   b.Measure Avo, Av@RL= 1K, Rin (input impedance) and Rout (output impedance) of the assembled circuit.

   c.Find the maximum input voltage that the amplifier can accept before the output distorts.

   d.Measure the phase relationship between the input and output voltages.
 
 
 

                                                                Figure # 2
 
 
 
 

3.- (Lab HW) Design of Common Drain

Design a Common Drain voltage amplifier with current mirror similar to the one shown in Fig # 2.  (Reference: Sedra & Smith section 5.7.3).

Design Specifications

1.  VDD = + 12 Volts DC

2.  ID = 10 mA

3.  |AV| = 1 (when loaded with RL= 1 k W )

4.  RIN ³ 750 KW

5.  ROUT £ 100 W

6.  Vout max (before distortion) ³ 4 Vpeak (loaded with RL=1kW)

• Show all design calculations.
• Use ORCAD to simulate the design
• Compare the ORCAD results to your design calculations and specifications and explain any and all differences.

4.- Assembly, Test and Verification of Specifications

Build and test your design. Measure and verify that your design meets all the given specifications.

   a.Measure VG, VS, VD, and ID with no small signal input.

   b.Measure Avo, Av@RL= 1K, Rin (input impedance) and Rout (output impedance) of the assembled circuit.

   c.Find the maximum input voltage that the amplifier can accept before the output distorts.

   d.Measure the phase relationship between the input and output voltages.
 
 

5.- Analysis

   a. Compare the measured results to your design calculations and specifications. Explain any and all differences.

   b. Write  equations and plot the AC and DC load line of Common Source and Common Drain.  Explain how to pick a good point for CSC and CDC from the AC and DC load line.  Example about picking good AC and DC line is in the lab handouts under "Design of Common Source" by Zvi Markowitz.

   c.  Is  the current source  design of the CDC (Fig. 2) a better choice compared to the configuration given in Fig. 1? If so, why?