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Question
Explain the current flow in an NPN transistor.
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Solution
- In NPN transistor electron flow from Emitter to the collector. So conventional current flow from collector to emitter.
- Electrons from the emitter region flow towards the base region constitute emitter current (IE). Electrons after reaching the base region recombine with holes – Most of the electrons reach the collector region. This constitutes collector current (IC). After recombination of holes in the base region by bias voltage VEE constitutes base current IB.
IE = IB + IC [Since base current is very low IC ≈ IC]
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