p-n-p

The PNP type triode is a triode tube composed of two N-type semiconductors sandwiched between two P-type semiconductors. The function of the PNP type transistor is similar to that of the NPN type. However, unlike the NPN type transistor, the PNP type connects the high potential to the emitter and the low potential to the collector. Therefore, the PNP type transistor can also be described as the triode with the current inflow from the emitter E.