# MOSFET Amplifier with CG Configuration – 1 MCQ’s

This set of Analog Electronic Circuits Multiple Choice Questions & Answers (MCQs) focuses on “MOSFET Amplifier with CG Configuration – 1″.

1. What is the input impedance of the following CG stage?

a) 1/gm
b) 2* Rs || 1/gm
c) Rs || 1/gm
d) Rs || 2/gm

2. If Channel Length modulation is neglected, what is the voltage gain from the source to the drain for the CG stage shown below?

a) gm * Rd * {2Rs / (Rs + 1/gm)}
b) gm * Rd * {Rs / (Rs + 2/gm)}
c) gm * Rd * {2Rs / (Rs – 1/gm)}
d) gm * Rd * {Rs / (Rs + 1/gm)}

3. In the following circuit, what is the voltage at the source of the M1?

a) Vin * Rs / (Rs + 1/gm)
b) Vin * Rs / (Rs + gm)
c) Vin * Rs / (Rs – 1/gm)
d) Vin * Rs / (Rs + 2/gm)

4. What is the input impedance for the following circuit?

a) ro
b) 1/gm
c) Rd || ro
d) Infinite

5. If channel length modulation is present, what is the output impedance of the following circuit?

a) Rd
b) Rd || ro
c) ro
d) 0

6. If channel length modulation is present. what is the overall output impedance of the following CG stage?

a) Rd || {Rs*(1+gm * ro) + ro}
b) Rd || {Rs*(1+gm * ro) + 2ro}
c) Rd || {Rs*(1+gm * ro) – ro}
d) Rd || {Rs*(2+gm * ro) + ro}

7. If channel length modulation is neglected, what is the voltage gain for the following circuit from source to drain?

a) gm * Rd
b) gm * ro
c) gm * (ro || Rd)
d) -gm * Rd

8. If channel length modulation is neglected, what is the voltage gain for the following CG stage?

a) Rd/(1/gm – Rs)
b) Rd/(3/gm + Rs)
c) Rd/(1/gm + Rs)
d) Rd/(2/gm + Rs)

9. The current gain of a simple CG stage is approximate ____________
a) Infinity
b) unity
c) twice
d) 0

10. If channel length modulation is neglected, what is the voltage gain of the following circuit?

a) – {gm1 * Rd * gm2 * Rd1}
b) gm1 * Rd * gm2 * 2Rd1
c) – {gm1 * Rd * 2gm2 * Rd1}
d) gm1 * 2Rd * gm2 * Rd1

11. If channel length modulation is neglected, what is the voltage gain for the following circuit?

a) – {gm1 * Rd * Rd / (1/gm2 + Rs)}
b) – (gm1 * 2Rd * Rd / Rs)
c) – {gm1 * Rd * Rd / (1/gm2 + Rs)}
d) – {gm1 * Rd * Rd / (1/gm2 + 2Rs)}

12. The voltage gain of a simple CG stage is greater than that of a follower.
a) True
b) False

13. If channel length modulation is present, what is the voltage gain of the following circuit?

a) gm1 * (Rd || ro1) * gm2 * Rd1
b) – {gm1 * Rd * gm2 * 2(Rd1 || ro2)}
c) – {gm1 * (Rd || ro1) * gm2 * (Rd1 || ro2)}
d) gm1 * 2Rd * gm2 * Rd1

14. If channel length modulation is neglected, what is the overall voltage gain of the following circuit?

a) – {gm1 * (Rd || 1/gm2) * (Rd1/ (1/gm2 + Rd))}
b) – {gm1 * (Rd || 1/gm2) * gm2 * 2Rd1}
c) – {gm1 * Rd * gm2 * Rd1}
d) – {gm1 * 1/gm2 * gm2 * Rd1}

15. If channel length modulation is neglected, what is the voltage gain of the following circuit?

a) gm2/gm1
b) – {gm2 * Rd * gm1 * R1}
c) Rd/gm2
d) 0