Question

explain the working of P.N.P and N.P.N transistors? pls give me short notes my friends help me pls​

Answer 1

NPN and PNP refer to the arrangement of the pieces that make up the transister. The practical result is the direction of current flow. An NPN transistor has a piece of P-type silicon (the base) sandwiched between two pieces of N-type (the collector and emitter). In a PNP transistor, the type of the layers are reversed.

Answer 2

As started before in n-p-n bipolar transistor one p-type semiconductor resides between two n-type semiconductors the diagram below a n-p-n transistor is shownNow IE, IC is emitter current and collect current respectively and VEB and VCB are emitter base voltage and collector base voltage respectively. According to convention if for the emitter, base and collector current IE, IB and IC current goes into the transistor the sign of the current is taken as positive and if current goes out from the transistor then the sign is taken as negative. We can tabulate the different currents and voltages inside the n-p-n transistor.