High-frequency switching power supply (also known as switching rectifier SMR) is a high-frequency power supply operated through MOSFET or IGBT. The switching frequency is generally controlled within the range of 50-100kHz to achieve high efficiency and miniaturization.

High frequency switching power supply working principle: switch K to a certain time interval repeatedly on and off, when the switch K is on, the input power E through the switch K and filter circuit supply to the load RL, during all switches on, power E to the load supply energy; When switch K is disconnected, power supply E interrupts the supply of energy. It can be seen that the input power supply to the load is intermittent. In order to make the load can be connected with the energy supply, the switch regulator power supply is necessary to have a set of energy storage equipment. When the switch is switched on, part of the energy is stored, and when the switch is disconnected, it is released to the load.