MOS transistor is one kind of FET (the other is JFET), which can be manufactured into enhanced or depletion type. There are four types of p-channel or n-channel, but only enhanced n-channel MOS transistor and enhanced p-channel MOS transistor are actually applied, so NMOS or PMOS are usually mentioned. NMOS is commonly used for these two enhanced MOS transistors. The reason is that the on resistance is small and easy to manufacture. Therefore, NMOS is generally used in switching power supply and motor drive applications. In the following introduction, NMOS is mainly used. MOS tube
