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  • Question

  • Assertion (A): PIN diode is used as a fast switch.

    Reason (R): PIN diode has very high resistance when reverse biased and very low resistance when forward biased.


  • Options
  • A. Both A and R are correct and R is correct explanation of A
  • B. Both A and R are correct but R is not correct explanation of A
  • C. A is correct but R is wrong
  • D. A is wrong but R is correct

  • Correct Answer
  • Both A and R are correct and R is correct explanation of A 

    Explanation
    A PIN diode has an intrinsic (i) layer between p and n layers. When reverse bias is applied depletion layers are formed at p-i and i-n junctions.

    The effective/width of depletion layer increases by the width of i layer. It can be used as a voltage controlled attenuator.

    At high frequencies the rectification effect ceases and impedance of diode is effectively that of i layer.

    This impedance varies with the applied bias. It is used in high frequency switching circuits, limiters, modulators etc.

    More questions

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    • A. SCR
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    • C. SCS
    • D. Shockley diode
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    • 2. Schrodinger wave equation is partial differential equation.

    • Options
    • A. True
    • B. False
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    • 3. The output frequency of a cycloconverter can be changed by changing the firing angle.

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    • A. True
    • B. False
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    • 4. Most of the memory chips in static RAM

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    • B. need 2 V supply
    • C. need 5 V supply
    • D. need 12 V supply
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    • 5. In crystalline solids, atoms are stacked in a regular manner.

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    • A. True
    • B. False
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    • Options
    • A. A, B, C, D, E, F, H
    • B. A E B F H C D
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    • A. A
    • B. Wb
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    • Options
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      • Discuss
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    • C. 5 x 10-3
    • D. 1.05 x 10-2
      • Discuss
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    • Options
    • A. Farads
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    • C.
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