ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 2
electron meet, they combine. For each electron that combines
with a hole, another electron leaves the negative terminal of
the battery, and enters the base. At the same time, an electron
leaves the emitter, creating a new hole, and enters the positive
terminal of the battery. This movement of electrons into the
base and out of the emitter constitutes base current flow (IB),
annd the path these electrons take is referred to as the
emitterbase circuit.
FIGURE 93. FORWARDBIASED JUNCTION IN A PNP TRANSISTOR.
(2) PNP ReverseBiased Junction. In the reversebiased
junction (figure 94 on the following page), the negative voltage
on the collector and the positive voltage on the base, block the
majority current carriers from crossing the junction. However,
this same negative collector voltage acts as forward bias for
the minority current holes in the base, which cross the junction
and the enter the collector. Theminority current electrons in
the collector react to forward bias the positive base voltage
and move into the base.
Previous Page
