Electronic Devices and Circuits Mid - II, November - 2014

1.For saturation of BJT of silicon
  • -∞ ≤ VCE ≤ 0.2
  • β VCE0 ≤ VCE ≤ 0.2
  • -∞ ≤ VCE ≤ 0
  • 0 ≤ VCE ≤ 0.2
Answer: A
2.Collector current and reverse saturation collector current are related as
  • IC > ICEO
  • IC < ICEO
  • IC = ICEO
  • None of the above
Answer: A
3.The Typical turn off time of transistor is
  • 10m sec
  • 60n sec
  • 70nsec
  • 40n sec
Answer: C
4.Which of the following transistor are affected by static electricity
  • UJIT
  • FET
  • MOSFET
  • NPN Transistor
Answer: C
5.ncase JFET and MOSFET
  • Bothrequires negative gate voltage Operation
  • JFET positive gate voltage and MOSFET negative gate voltage
  • JFET negative gate voltage and MOSFET positive gate voltage
  • None of the above
Answer: C
6.JFET operates on
  • Depletion mod
  • Enhancement mode
  • Both A & B
  • Neither A or B
Answer: A
7.The Pinch- off voltage for a JFET is 4v,when VGS = 1, the pinch –off occurs for VDS is equal to
  • 3v
  • 5v
  • 4v
  • 1v
Answer: D
8.The thermal run away will takes pla ce if the quescient point is such that
  • VCC == VCE
  • VCC == 2VCE
  • 1/2 VCC == VCE
  • VCE < 1/2 VCC
Answer: D
9.A J FET uses set up as source follower having rd = 100K, = 200 & load resistance as 1K, the output impedance is
  • 333 ohms
  • 0.98 ohms
  • 0.882 ohms
  • 0.682 ohms
Answer: A
10.In order toachive good stabilization in potential divider bias method current through R1 & R2 should be at least _________ times IB
  • ≥ 10
  • < 10
  • ≠ 10
  • None of the above
Answer: A
11.In BJT, Large signal current gain _______________________
Answer:  = (IC - ICEO) / IB,
12.The cut in voltage Vr is _________________
Answer: Is the forword bias voltage below which the current is very small
13.In UJT, Intrinsic stan off ratio lies between __________ to _________
Answer: 0.5, 0.8
14.The point of inter section of a.c load line is called __________________
Answer: Operating point
15.For the typical transistor amplifier in active region VCE is usually about ___ % to ___ %of IB
Answer: 25%, 75%
16.h-parameters valid for _______ region of frequency range.
Answer: Radio, 7
17.If the temperature increases the value of VBE _______________.
Answer: Is decreased
18.The disadvantage of voltage divide bias is that it has ___________________.
Answer: Many resistors
19.The value of S for fixed bias circuit is _________________.
Answer: s = 1 +
20.CB amplifier has voltge gain is _______ for normal RL values
Answer: highest