Generally, it is a metal oxide semiconductor field-effect transistor, or also known as a metal insulator semiconductor. G: Gate gate; S: Source source; D: Drain drain. The source and drain of MOS transistors can be swapped, both of which are N-type regions formed in P-type backgate. In most cases, these two regions are the same, and even if the two ends are switched, it will not affect the performance of the device. Such devices are considered symmetrical.
