Even though mechanisms that makes bipolar transistor run are quite complica ted and there are many side effect to be covered, simple analysis is possi ble with two simple models: one for active regime, when we use one independ ent voltage source to model base-emitter p-n junction and one current contr olled current source to model collector-emitter junction. Another is model of bipolar transistor that takes only two independent voltage sources. Read more.
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