A type of transmitter that allow electricity to flow from the collector to the emitter only when electricity at the base is below a trigger voltage (usually 3 volts or 5 volts).
A bipolar junction transistor in which a p-type base element is sandwiched between an n-type emitter and an n-type collector.
A two-junction transistor with an N-type collector and emitter and a P-type base. See bipolar transistor and complementary. Compare PNP transistor.