Electronics and Communication Engineering - Analog Electronics

16. 

Values of VT at 20°C for an ideal P-N diode

A. 25.27 mV
B. 30.3 mV
C. 23 mV
D. 50 mV

Answer: Option A

Explanation:

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17. 

Assertion (A): In an op-amp the voltage gain and band width can be adjusted as per requirement

Reason (R): Large value capacitor can also be fabricated on a chip

A. Both A and R are correct and R is correct explanation for A
B. Both A and R are correct but R is not correct explanation for A
C. A is correct R is wrong
D. A is wrong R is correct

Answer: Option C

Explanation:

Large value capacitor cannot be fabricated on a chip.


18. 

In figure which diode will conduct and what will be the value of V0?

A. D3, 1 V
B. D1, 2 V
C. D2, 5 V
D. D1, 5 V

Answer: Option C

Explanation:

Since battery connected to anode of D, is of 5 V it is forward biased. D1 and D3 are reverse biased. Output voltage is 5 V.


19. 

For the amplifier circuit of figure, the h parameters of transistor are hib = 25 Ω, hfb = 0.999, hob = 10-6 Ω. The voltage gain is

A. 0.999
B. 1.98
C. 20
D. 400

Answer: Option D

Explanation:

It is a common base circuit .


20. 

In figure, VCC = + 30 V, R1 = 200 kΩ and R2 = 100 kΩ. If VBE = 0.7 V, the voltage a cross RE =

A. +20 V
B. +19.3 V
C. +10 V
D. +9.3 V

Answer: Option D

Explanation:

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