Power Transistor concept

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Power Transistor

Concept

  • A power transistor possesses a high blocking voltage capability in the OFF state and high current carrying capability in the ON state. They are normally used as switch. 
  • Power transistors are available in both NPN and PNP forms. But the available current and voltage ratings are higher for NPN devices. Because of the greater mobility of electrons compared with holes, NPN devices can be fabricated on a smaller chip area to provide the same performance as that of an equivalent (counterpart) PNP devices. 
  • The power transistor with current ratings of several hundred amperes and voltage ratings of several hundred volts are presently available in Market.
  • The symbol for power transistor is same as low power transistor: (1) NPN (2) PNP 


Symbol of NPN and PNP Transistor
Symbol of NPN and PNP Transistor


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