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Which of the following statements about pnpn diode is FALSE?

Which of the following statements about pnpn diode is FALSE? Correct Answer This device works as a switch and is fabricated to have current ratings of several hundred volts.

Shockley Diode or PNPN Diode:

  • The Shockley diode or PNPN diode is a four-layer (P-N-P-N), two-terminal semiconductor switching device.
  • It is also called a four-layer or three junction diode.
  • It works as a normal diode without any trigger inputs like SCRs.
  • In reverse biased condition, no current flows through it, and in forwarding biased condition current flows through it when the voltage across it is more than the break over voltage of it.
  • These diodes have only two states, either ON or OFF hence it is considered as the first member of the thyristor family.
  • PNPN diodes have relatively low reverse voltage ratings and their relatively high reverse leakage current. For example, silicon-metal diodes have a rating of about 50 V or less.
  • The basic construction, two-transistor analogy, and symbol of the Shockley diode are shown below.

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  • PNPN diodes are used mainly for switching applications such as relaxation oscillators and trigger switches.

Related Questions

When the pnpn diode is biased such that the p side is more positive than the n side, the junctions I1 and I3 are:
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