How to use letters to represent the tertiary tube

The triode has three electrodes as its name implies. The diode is made of a PN structure, and the triode is made of two PN structures, and the shared electrode becomes the base of the triode (indicated by the letter b). The other two electrodes become the collector (indicated by the letter c) and the emitter (indicated by the letter e). Due to different combinations, one is an NPN-type transistor and the other is a PNP-type transistor.
Transistor, the full name should be semiconductor triode, also known as bipolar transistor, transistor, is a kind of semiconductor device that controls current. Its function is to amplify weak signal into electric signal with larger amplitude, and also used as contactless switch. Transistor is one of the basic semiconductor components. It has the function of current amplification and is the core component of electronic circuits. The triode is made of two PN junctions very close to each other on a semiconductor substrate. The two PN junctions divide the entire semiconductor into three parts. The middle part is the base area, and the two sides are the emitter and collector areas. The arrangement is PNP And NPN two kinds.

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