
Semiconductor Components
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8.6.4 Cutoff Mode
The emitter-base junction is not forward biased if
γ
VV V0.7
BE
. In particular
both junctions are reverse-biased (or no biased at all), both I
and I
currents
are in the order of the reverse saturation current and, for the most part of applica-
tions, can be neglected.
In such conditions, the BJT behaves approximately as an open-circuit (Section
6.1.1 in Chapter 6).
Given an npn−type BJT, when the emitter-base junction is not forward biased,
namely reverse biased or no biased at all, and the base-collector junction is reverse
biased, the BJT is said to work in cutoff mode.
8.6.5 Saturation Mode
With ...