EE401_Quiz1

In a common-source amplifier, the output voltage is

• 180 degree out of phase with the input

• in phase with the input

• taken at the source

• taken at the drain

In a certain common-source (CS) amplifier, Vds = 3.2 V rms and Vgs = 280 mV rms. The voltage gain is

• 1

• 11.4

• 8.75

• 3.2

Ideally, the equivalent circuit of a FET contains

• a current source in series with a resistance

• a resistance between drain and source terminals

• a current source between gate and source terminals

• a current source between drain and source terminals

The value of the dependent current source in small signal circuit circuit of a CS Amplifier is dependent on the

• transconductance and gate-to-source voltage

• dc supply voltage

• external drain resistance

• None of the answers

A CS amplifier has a load resistance of 10 k and RD = 820 . If gm = 5 mS , Vin= 500 mV, the output signal voltage is

(a) 1.89 V (b) 2.05 V (c) 25 V (d) 0.5 V

• 2.05 V

• 1.89 V

• 25 V

• 0.5 V

A certain common-drain (CD) amplifier with has RS = 1.0 k and a transconductance of 6000 uS. The voltage gain is

• 1

• 0.86

• 0.96

• 6

The common-gate (CG) amplifier differs from both the CS and CD configurations in that it has a

• much higher voltage gain

• much lower voltage gain

• much higher input resistance

• much lower input resistance

If you are looking for both good voltage gain and high input resistance, you must use a

• CS amplifier

• CD amplifier

• CG amplifier

• None of the answers

The lowest output resistance among the following configuration is

• CD

• CG

• CS

• None of the answers

The lowest input resistance among the following configuration is

• CD

• CG

• CS

• None of the answers