“Si” is one of the most commonly used semiconductor, and NPN transistors are the easiest transistors to make out of silicon. For an NPN transistor to work properly, it needs to be formed from a semiconductor material, which carries some electric current, but not the maximum amount as very conductive materials like metal. Generally, this transistor is used because it is so easy to produce. But the applications of the voltages or currents in terms of polarity are different. The working operation is similar to that of n-p-n. The majority of the carriers those are responsible for the generation of the current are in this transistor are holes. The p-n-p transistors are formed with n-type present in between the p-types. The fundamental difference between a PNP and a PN transistor is the proper biasing of the transistor junctions the current directions and the voltage polarities are always opposite to each other. To cause the base current to flow during a PNP transistor, the base terminal must be more negative than the emitter terminal by approx. The base voltage VB is connected to the base resistor RB, which is biased negative with respect to the emitter. The emitter is connected to the Vcc with the RL, this resistor limits the max current flowing through the device, which is connected to the collector terminal. The voltage sources are connected to a PNP transistor, which is shown in the figure. Also, the emitter voltage is positive with respect to the collector (VCE). The characteristics of both PNP and NPN transistors are similar except that the biasing of the voltage and current directions are reversed for any one of the possible three configurations such as a common base(CB), common emitter(CE) and common collector(CC).The voltage between the base and emitter terminal VBE is negative at the base terminal and positive at the emitter terminal because for a PNP transistor, the base terminal always biased negative with respect to the emitter. The PNP transistor configuration is shown below. Therefore, the base terminal of the PNP transistor must be negative with respect to the emitter terminal, and the collector must be negative than the base. The base-collector terminals of the PNP transistor are always reversed biased, then the negative voltage must be used for the collector. The PNP transistor bias setup is shown in the below figure. The materials which are used to construct the emitter, base and collector terminals in the PNP transistor are different from those used in the NPN transistor. Basically, this transistor works the same as the NPN transistor. ![]() In this type of transistor, the majority charge carriers are holes. ![]() The working of PNP transistor is the exact opposite to the NPN transistor. The PNP transistor is a bipolar junction transistor In a PNP transistor, the first letter P indicates the polarity of the voltage required for the emitter the second letter N indicates the polarity of the base. But, field effect transistors have only one type of charge carrier.ĭifference between NPN and PNP Transistors and their Making PNP Transistor In PNP transistors, majority charge carriers are holes, whereas in NPN transistors, electrons are the majority charge carriers. Bipolar junction transistors can be found either as large numbers as parts of integrated circuits or in discrete components. These transistors are used as switches, amplifiers or oscillators. The PNP and NPN transistors allow current amplification. The operation of these transistors involves both electrons and holes. ![]() NPN and PNP transistors are bipolar junction transistors, and it is a basic electrical and electronic component which is used to build many electrical and electronic projects. The most frequent one among its applications is it’s fully ON and the OFF operating mode which is referred to as switch. These are used in the various amplifications circuits and the modulating circuits. Both p-n- p and the n- p-n transistors are the basic transistors which come under the category of bipolar junction transistors.
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