![]() ![]() The key to the fabrication of a transistor is to make the middle layer, the base, as thin as possible without shorting the outside layers. When changing the bias of the transistor, the width of the depletion layers of the base-emitter and base-collector junctions will change.The base of a transistor is lightly doped and very thin due to which it offers the majority charge carrier to the base. The collector section of the transistor is moderately doped, but larger in size so that it can collect most of the charge carrier supplied by the emitter. The width of base is kept small because as we know it is lightly doped & contains less charge carries & requires less current (2-5) to flow in base region & for collection of maximum charge carries coming from emitter in collector as base offers less resistance hence it's width is small. The emitter of a transistor is heavily doped and moderate in size. The emitter-base is forward-biased and offers low resistance to the circuit. The base forms two circuits, the input circuit with the emitter, and the output circuit with the collector. The collector-base junction is always reverse biased. The emitter is always forward biased with respect to the base so that it supplies the majority charge carrier to the base. As you can see on the datasheet below for the 2n2222a NPN transistor, the 'Collector-Emitter Saturation Voltage' and 'Base-Emitter Saturation Voltage' are defined respectively as 0.3 to 1.0 and 1.2 to 2.0. Touch the negative probe to the pin-1 (Emitter). Base region of a transistor is kept very small and very lightly doped so as to pass most of the injected charge carriers to the collector. Keep the positive probe to the center pin (Base) of the transistor. This is because the work of the emitter is to supply charge carrier to. ![]() The collector-base junction is in reverse bias and offers higher resistance to the circuit. Steps to identify the NPN type transistor: Keep the Multimeter in the Diode mode. Emitter: Emitter terminal is the heavily doped region as compared two base and collector. The middle section of the transistor is known as the base. In a transistor, the section that collects the majority of the charge carrier supplied by the emitter is called a collector. In a transistor, emitter supplies a large section of majority charge carriers. These three terminals are known and labelled as the Emitter ( E ), the Base ( B ) and the Collector ( C ) respectively.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |