Semiconductor triode
1. Structure and type
(1) Structure
Triode is composed of two PN junctions (collecting junction, emitting junction), three regions (collecting region, base region, emitting region), and three electrodes (collector, base and emitter).
(2) Type
It can be divided into NPN type and PNP type. The direction of the emitter arrow indicates the direction of the current when the emitter junction is positively biased. The character symbol is VT.
2. Current amplification of triode
(1) Conditions
To make the triode in the magnifying state, it is necessary to ensure the positive bias of the transmitting junction and the negative bias of the collector junction.
(2) Current amplification