ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 2
will have a far greater effect on the magnitude of collector
current than it will have on base current. In conclusion, the
relatively small emitterbase bias controls the relatively large
emittertocollector current.
g. PNP Transistor Operation. PNP transistor operation is
essentially the same as the NPN operation except the majority
current carriers are holes and the bias batteries are reversed.
Figure 92 shows a typical bias setup for the PNP transistor.
FIGURE 92. PROPERLY BIASED PNP TRANSISTOR.
(1) PNP ForwardBiased Junction. What happens when the
emitterbase junction in figure 93, on the following page, is
forward biased. With the bias setup shown, the positive
terminal of the battery repels the emitter holes toward the
base, while the negative terminal drives the base electrons
toward the emitter. When an emitter hole and a base
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