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Except at high frequencies of switching, nearly all the power dissipated in the switch mode operation of a BJT occurs, when the transistor is in the

Except at high frequencies of switching, nearly all the power dissipated in the switch mode operation of a BJT occurs, when the transistor is in the Correct Answer Hard saturation region

Operation of BJT:

Region of operation

Application

Saturation

Cut-off

Active

Reverse Active

BJT used as ON switch

BJT used as OFF switch

BJT used as an amplifier

BJT used as ON switch

 

V-I characteristics of a common-emitter configuration of BJT as shown:

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In the hard-saturation region, the ON time duration is more. ∴ the power dissipation occurs in large amounts as the current is maximum.

In the cut-off region current is zero. So no power dissipation occurs in this region during the switched-mode operation of BJT.

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