

Voltage polarity: The voltage polarities for the power supplies and input/output signals are reversed for PNP and NPN transistors. For a PNP transistor, the base-emitter junction is reverse-biased and the collector-base junction is forward-biased. For an NPN transistor, the base-emitter junction is forward-biased and the collector-base junction is reverse-biased. In a PNP transistor, the current flows from the emitter to the collector, and the base-emitter junction is reverse-biased.īiasing: NPN and PNP transistors require different biasing arrangements. The direction of current flow: In an NPN transistor, the current flows from the collector to the emitter, and the base-emitter junction is forward-biased. In a PNP transistor, the base region is made of a thin layer of N-type semiconductor material, while the collector and emitter regions are made of P-type semiconductor material. Differences Between PNP And NPN Transistors:Ĭonstruction: In an NPN transistor, the base region is made of a thin layer of P-type semiconductor material, while the collector and emitter regions are made of N-type semiconductor material. The collector is moderately doped and large in size. The majority of charges emitted by the emitter are collected by the collector.

The base of a transistor is lightly doped, and its dimension is very thin.Ĭollector: the other P-type region is the collector terminal in the PNP transistor. The emitter is highly doped and moderate in size.īase: The central region is known as the base terminal, which is an N-type region in the PNP transistor. This supplies major charge carriers, which are holes in the PNP transistors. Emitter: One of the p-type regions is the emitter terminal in the PNP transistor.
