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The double base diode which is operated with the emitter forward biased and a smaller emitter junction is called.

The double base diode which is operated with the emitter forward biased and a smaller emitter junction is called. Correct Answer Uni-Junction Transistor (UJT)

Uni-Junction Transistor:

  • UJT or P-N transistor is a two-layer P-N device with three terminals known as emitter, base-1 (B1) and base-2 (B2)
  • Similar to BJT, UJT is fabricated on a lightly doped N-type silicon bar with ohmic contacts for two base terminal B1 and B2 at the top and lower ends of the bar.
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  • It exhibits negative resistance characteristic i.e. increase in emitter current results in a decrease of voltage between the emitter E and B1 terminals.
  • Negative Resistance property of the device is made use of the relaxation oscillation circuit.
  • Main different of FET and UJT is that gate surface of FET is much larger than the Emitter Junction of UJT
  • FET is normally operated with gate junction reverse-biased, where useful behavior of UJT occurs when the emitter is forward biased.
  • UJT was originally known as a double-base diode.
  • The emitter section is a heavily doped P-type material that is deposited between Base B1 & B2, possessing only one P-N Junction of the small area.

Related Questions

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