NPN is one of the two types of bipolar transistors, the second being PNP. The letters "N" and "P" refer to the majority charge carriers inside the different regions of the transistor. Most transistors used today are NPN, since this is the easiest and most cost effective to make from silicon. The schematic symbols for PNP- and NPN- type BJTs. ... Plug and Play is a term used in the computer field to describe a computers ability to have new devices, normally peripherals, added to it without having to restart the computer. ... General Name, Symbol, Number silicon, Si, 14 Chemical series metalloids Group, Period, Block 14, 3, p Appearance dark gray, bluish tinge Atomic mass 28. ...

NPN transistors consist of a layer of P-doped (the doping agent is often boron) semiconductor (the "base") between two N-doped (often made with arsenic) layers. NPN transistors are commonly operated with the emitter at ground and the collector at a positive voltage. Doping is generally the practice of adding impurities to something. ... General Name, Symbol, Number boron, B, 5 Chemical series metalloids Group, Period, Block 13, 2, p Appearance black/brown Atomic mass 10. ... A semiconductor is a material with an electrical conductivity that is intermediate between that of an insulator and a conductor. ... General Name, Symbol, Number arsenic, As, 33 Chemical series metalloids Group, Period, Block 15, 4, p Appearance metallic gray Atomic mass 74. ... An emitter is any device used to emit any signal, beacon, light, odor, liquid, fragrance, or the like. ... Ground symbols The term ground (or earth) usually means a common return path in electrical circuits. ... This article may be too technical for most readers to understand. ...

See also

• Transistor