Deck 5: Electrical Engineering Circuit Analysis

Question 1

For the circuit shown below express v0 as a function of v1 and v2.

A)v0 = v1 + v2
B)v0 = v2 - v1
C)v0 = v1 - v2
D)v0 = -v1 - v2

Answer 1

v0 = v2 - v1

Question 2

Determine Ad and Ac for the given circuit.

A)ac = 0 and ad = 1
B)ac ? 0 and ad = 1
C)ac = 0 and ad ? 1
D)ac ? 0 and ad ? 1

Answer 2

ac = 0 and ad = 1

Question 3

Determine the voltage gain for the given circuit known that R1 = R3 = 10k? abd R2 = R4 = 100k?.

A)1
B)10
C)100
D)1000

Answer 3

10

Question 4

What is trans-conductance?

A)ratio of change in drain current to change in collector current
B)ratio of change in drain current to change in gate to source voltage
C)ratio of change in collector current to change in drain current
D)ratio of change in collector current to change in gate to source voltage

Question 5

What is the value of trans conductance?

A)1
B)2
C)0.1
D)0.01

Question 6

002. What is the value ofgm?

A)1
B)2
C)0.002
D)0

Question 7

Find the maximum value of gm for FET with IDSS=10mA, Vp=-2V, VGS=5V?

A)10ms
B)20ms
C)1ms
D)0

Question 8

A FET has IDSS=4ID and gm0 = 10mS then gm =                                                    

A)10ms
B)20ms
C)5ms
D)14ms

Question 9

Determine the value of output impedance for JFET, if the value of gm =1mS?

A)1kohm
B)0
C)100kohm
D)5kohm

Question 10

In a small signal equivalent model of an FET, What does gm VGS stand for?

A)a pure resistor
B)voltage controlled current source
C)current controlled current source
D)voltage controlled voltage source

Question 11

Given yfs = 3.6mS and yos = 0.02mS, determine r0?

A)100kohm
B)50mohm
C)50kohm
D)20kohm

Question 12

Which of the following statement is incorrect?

A)output of ce amplifier is out of phase with respect to its input
B)cc amplifier is a voltage buffer
C)cb amplifier is a voltage buffer
D)ce amplifier is used as an audio (low frequency) amplifier

Question 13

Given hfe = 60, hie=1000?, hoe = 20? ?-, hre = 2 * 10-4. Find the current gain of the BJT, correct up to two decimal points.

A)- 58.44
B)-59.21
C)- 60.10
D)- 60.00

Question 14

Consider the circuit. Given hfe = 50, hie = 1200?. Find voltage gain.

A)- 278
B)-277.9
C)- 300
D)- 280

Question 15

Given that IB = 5mA and hfe = 55, find load current.

A)28ma
B)280ma
C)2.5a
D)2a

Question 16

Consider the following circuit, where source current = 10mA, hfe = 50, hie = 1100?, then for the transistor circuit, find output resistance RO and input resistance RI.

A)ro = 0, ri = 21?
B)ro = ?, ri = 0?
C)ro = ?, ri = 21?
D)ro = 10, ri = 21?

Question 17

For the given circuit, input resistance RI = 20?, hfe = 50. Output resistance = ?. Find the new values of input and output resistance, if a base resistance of 2k? is added to the circuit.

A)ri = 20?, ro = ?
B)ri = 20?, ro = 2k?
C)ri = 59?, ro = ?
D)ri = 59?, ro = 2k?

Question 18

If source resistance in an amplifier circuit is zero, then voltage gain (output to input voltage ratio) and source voltage gain (output to source voltage ratio) are the same.

Question 19

The Differential output of the difference amplifier is the amplification of                      

A)difference between the voltages of input signals
B)difference between the output of the each transistor
C)difference between the supply and the output of the each transistor
D)all of the mentioned

Question 20

The inputs to the differential amplifier are applied at                      

A)at x and y
B)at the gates of m1 and m2
C)all of the mentioned
D)none of the mentioned

Question 21

In Common Mode Differential Amplifier, the outputs Vout1 and Vout2 are related as:

A)vout2 is in out of phase with vout1 with same amplitude
B)vout2 and vout1 have same amplitude but the phase difference is 90 degrees
C)vout1 and vout2 have same amplitude and are in phase with each other and their respective inputs
D)vout1 and vout2 have same amplitude and are in phase with each other but out of phase with their respective inputs

Question 22

In a small signal differential gain vs input CM level graph, the gain decreases after V2 due to:

A)as the input voltage increases, the output will be clipped
B)when the input voltage to the transistors are high, the transistor enters saturation region and increases the current, which inturn decreases the output voltage = vdd - rd.iss
C)when common mode voltage is greater than or equal to v2, the input transistors enter triode region, the gain begins to fall
D)increasing the input voltage beyond v2 causes the gate oxide to conduct and the gain is reduced

Question 23

Consider a voltage amplifier having a frequency response of the low-pass STC type with a dc gain of 60 dB and a 3-dB frequency of 1000 Hz. Then the gain db at

A)f = 10 hz is 55 db
B)f = 10 khz is 45 db
C)f = 100 khz is 25 db
D)f = 1mhz is 0 db

Question 24

STC networks can be classified into two categories: low-pass (LP) and high-pass (HP). Then which of the following is true?

A)hp network passes dc and low frequencies and attenuate high frequency and opposite for lp network
B)lp network passes dc and low frequencies and attenuate high frequency and opposite for hp network
C)hp network passes dc and high frequencies and attenuate low frequency and opposite for lp network
D)lp network passes low frequencies only and attenuate high frequency and opposite for hp network

Question 25

The signal whose waveform is not effected by a linear circuit is

A)triangular waveform signal
B)rectangular waveform signal
C)sine/cosine wave signal
D)sawtooth waveform signal