Home / ECE / Analog Electronics :: Section 21

ECE :: Analog Electronics

  1. In a BJT amplifier circuit the size of coupling capacitor depends on

  2. A.
    lowest frequency
    B.
    highest frequency
    C.
    average of lowest and highest frequencies
    D.
    none of the above

  3. In a closed loop non-inverting amplifier, constructed using single break-frequency op-amp, bandwidth with feedback can be written as. (f0 - break frequency, β - gain of the feedback circuit, A - open loop voltage gain, Af - closed loop voltage gain)


  4. A silicon sample A is doped with 1018 Atoms/cm3 of Boron. Another sample B of identical dimensions is doped with 1018 atoms/cm3 of phosphorus. The ratio of electron to hole mobility is 3. The ratio of conductivity of the sample A to B is

  5. A.
    3
    B.
    1/3
    C.
    2/3
    D.
    3/2

  6. Which of the following circuit has the greatest bandwidth?

  7. A.
    fr = 455 MHz; Q = 10
    B.
    fr = 455 MHz; Q = 100
    C.
    fr = 1 MHz; Q = 100
    D.
    fr = 1 MHz; Q = 10

  8. A FET is a __________ controlled device whereas a bipolar transistor is a __________ controlled device.

  9. A.
    gate, drain
    B.
    drain, gate
    C.
    current, voltage
    D.
    voltage, current

  10. Two identical FETs, each characterised by the parameters gm and rd are connected in parallel. The composite FET is then characterised by the parameters

  11. A.
    and 2rd
    B.
    and
    C.
    2gm and
    D.
    2gm and 2rd

  12. Assertion (A): If power gain doubles the power gain increases by 3 dB

    Reason (R): The bel power gain of cascaded stages is equal to sum of each bel power gain

  13. 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

  14. The V MOS can handle __________ currents than a conventional MOSFET.

  15. A.
    much lower
    B.
    almost same
    C.
    almost half
    D.
    much larger

  16. Assertion (A): A resistor is a passive load and a transistor is an active load

    Reason (R): Op-amp is mostly used in feedback mode

  17. 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

  18. Which mode is usually preferred for cascading?

  19. A.
    CE
    B.
    CB
    C.
    CC
    D.
    Any of the above