Home / ECE / Electronic Devices and Circuits :: Section 5

ECE :: Electronic Devices and Circuits

  1. The maximum power handling capacity of a resistor depends on

  2. A.
    total surface area
    B.
    resistance value
    C.
    thermal capacity of the resistor
    D.
    resistivity of the material used in the resistor

  3. Epitaxial growth is used in ICs

  4. A.
    because it produces low parasitic capacitance
    B.
    because it yields back to back isolating pn Junction
    C.
    to grow single crystal n doped silicon on a single crystal P-type substrate
    D.
    to grow Selectivity single crystal P doped silicon of one resistivity on a P type substrate of a different resistivity

  5. The mean life time of carrier may range from 10-9 seconds to hundreds of μ-seconds.

  6. A.
    True
    B.
    False

  7. In which mode of BJT operation are both junctions forward biased?

  8. A.
    Active
    B.
    Saturation
    C.
    Cut off
    D.
    Reverse active

  9. Addition of a small amount of antimony to germanium will result in

  10. A.
    formation of P-type semiconductor
    B.
    more free electrons than holes in the semiconductor
    C.
    antimony concentrating on the edges of the crystals
    D.
    increased resistance

  11. In intrinsic semiconductor magnitude of free electron and hole concentrations are equal.

  12. A.
    True
    B.
    False

  13. A P-N junction offers

  14. A.
    high resistance in forward as well as reverse direction
    B.
    low resistance in forward as well as reverse direction
    C.
    conducts in forward direction only
    D.
    conducts in reverse direction only

  15. In modern MOSFETS, the material used for the gate is

  16. A.
    high purity silicon
    B.
    high purity silica
    C.
    heavily doped polycrystalline silicon
    D.
    epitaxial grown silicon

  17. Consider the following circuit configuration

    1. common Emitter
    2. common Base
    3. emitter follower
    4. emitter follower using Darlington pair.
    The correct sequence in increasing order of I/P impedance of these configuration:

  18. A.
    2, 1, 4, 3
    B.
    1, 2, 4, 3
    C.
    2, 1, 3, 4
    D.
    1, 2, 3, 4

  19. Assertion (A): Field emission is substantially independent of temperature.

    Reason (R): When a high electric field is created at metal surface field emission may occur.

  20. A.
    Both A and R are true and R is correct explanation of A
    B.
    Both A and R are true but R is not a correct explanation of A
    C.
    A is true but R is false
    D.
    A is false but R is true