Home / ECE / Analog Electronics :: Section 7

ECE :: Analog Electronics

  1. Assertion (A): An op-amp amplifier can amplify dc signal

    Reason (R): An op-amp amplifier is a direct coupled amplifier

  2. 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

  3. The most common method for biasing a JFET is

  4. A.
    reverse bias
    B.
    self bias
    C.
    voltage divider bias
    D.
    none of the above

  5. Which of the following figures is an ideal equivalent circuit of a n-p-n transistor?

  6. A.
    figure A
    B.
    figure B
    C.
    figure C
    D.
    none

  7. Which op-amp circuit uses a capacitor in series with input and resistance in feedback path?

  8. A.
    Differentiating amplifier
    B.
    Integrating amplifier
    C.
    Logarithmic amplifier
    D.
    None of the above

  9. For class B operation the theoretical maximum efficiency is

  10. A.
    100%
    B.
    78.5%
    C.
    50%
    D.
    27.5%

  11. Typical values of current gains for CE, CB and CC amplifiers are

  12. A.
    120, 120 and 1 respectively
    B.
    120, 1 and 120 respectively
    C.
    1, 120 and 120 respectively
    D.
    1, 1 and 120 respectively

  13. To draw ac equivalent circuit for a CE amplifier we should

  14. A.
    Reduce all dc sources to zero
    B.
    Short all capacitors
    C.
    Reduce all dc sources to zero and short all capacitors
    D.
    Reduce all dc sources to zero and open all capacitors

  15. In the circuit of figure, the value of re is (neglecting vbe)

  16. A.
    100 Ω
    B.
    75 Ω
    C.
    50 Ω
    D.
    25 Ω