EDC viva Questions

UNIT-7

1.Transistor can be treated as a two port network.( True/False)

 Ans: True

2. Z-parameters are also known as______                             

a) Impedance parameters        b) Admittance parameters

c) Hybrid parameters              d) closed Ckt parameters

Ans: (a)

3. y-parameters are also known as______                             

a) Impedance parameters        b) Admittance parameters

c) Hybrid parameters              d) Open Ckt parameters

Ans: (b)

4. h-parameters are also known as______                             

a) Impedance parameters        b) Admittance parameters

c) Hybrid parameters              d) closed Ckt parameters

Ans: (c)

5. For Z-parameters _______ are independent variables.

a) i₁                    b) i₂                  c) both (a)&(b)            d) v₂

Ans: (c)

6. For Y-parameters _______ are independent variables.

a) v₁                  b) v₂                 c) both (a)&(b)            d) i₂

Ans: (c)

7. For h-parameters _______ are independent variables.

a) i₁                    b) v₂                 c) both (a)&(b)            d) i₂

Ans: (c)

8. The dimensions of h₁₁ are  Ω .

9. The dimensions of h₂₂ are  mhos.

10. The dimensions of h_12,  h₂₁ are  dimensionless.

11. The dimensions of Z-parameters  are  Ω .

12. The dimensions of Y-parameters are mhos.           

13. Z-parameters are also known as Open ckt parameters.

14. y-parameters are also known as closed ckt parameters.

15.Formula for y₂₂= i₂/ v_2.

16. Formula for h₁₂= v₁/ v_2.

17. Formula for z₁₂= v₁/ i_2.

18. Current gain of CE-amplifier = -h_fe/(1+h_oe  z_L).

19. Voltage gain of CE-amplifier=  A_I z_L/ z_i.

20. Voltage gain of CB-amplifier=131.

UNIT-8

1.  Schottky diodes are also known as A. PIN diodes. B. hot carrier diodes. C. step-recovery diodes. D. tunnel diodes. Answer: Option B
	2.  Zener diodes with breakdown voltages less than 5 V operate predominantly in what type of breakdown?
	A. avalanche B. zener C. varactor D. Schottky Answer: Option B
			3.	The Schottky diode is used
				A. in high-power circuits. B. in circuits requiring negative resistance. C. in very fast-switching circuits. D. in power supply rectifiers. Answer: Option C

4.	You have an application for a diode to be used in a tuning circuit. A type of diode to use might be
	A. an LED. B. a Schottky diode. C. a Gunn diode. D. a varactor. Answer: Option D
5.	Refer to this figure. Which symbol is correct for an LED?
	A. a B. b C. c D. d E. e Answer: Option A 6.  Refer to this figure. If VIN increases, IZ will A. increase. B. decrease. C. remain the same. Answer: Option A 7.  What kind of diode is formed by joining a doped semiconductor region with a metal? A. laser B. tunnel C. pin D. Schottky Answer: Option D 8.  Refer to this figure. Which symbol is correct for a zener diode? A. a B. b C. c D. d E. e Answer: Option B 9.  Which diode employs graded doping? A. zener B. LED C. tunnel D. step-recovery Answer: Option D 10: Refer to this figure. Identify the Schottky diode. A. A B. b C. c D. d E. e Answer: Option E 11.  LEDs are made out of A. silicon. B. germanium. C. gallium. D. silicon and germanium, but not gallium. Answer: Option C 12.  The normal operating region for a zener diode is the A. forward-bias region. B. reverse-bias region. C. zero-crossing region. D. reverse-breakdown region. Answer: Option D 13.Refer to this figure. If VIN attempts to increase, VR will A. increase. B. decrease. C. remain the same. Answer: Option A 14.  An LED is forward-biased. The diode should be on, but no light is showing. A possible trouble might be A. the diode is open. B. the series resistor is too small. C. none. The diode should be off if forward-biased. D. the power supply voltage is too high. Answer: Option A 15.  A 6.2 V zener is rated at 1 watt. The maximum safe current the zener can carry is A. 1.61 A. B. 161 mA. C. 16.1 mA. D. 1.61 mA. Answer: Option B 16.  The process of emitting photons from a semiconductive material is called A. photoluminescence. B. gallium arsenide. C. electroluminescence. D. gallium phosphide. Answer: Option C 17.  What diode operates only with majority carriers? A. laser B. tunnel C. Schottky D. step-recovery Answer: Option C 18. What type of diode maintains a constant current? A. LED B. zener C. current regulator D. pin E. none of the above Answer: Option C 19. What diode is used in seven-segment displays? A. zener B. LED C. laser D. Schottky Answer: Option B 20.What type of diode is commonly used in electronic tuners in TVs? A. varactor B. Schottky C. LED D. Gunn Answer: Option A