Switching power supply (Switch Mode Power Supply, SMPS for short), also known as switching power supply, switching converter, is a high-frequency electric energy conversion device, which is a kind of power supply. Its function is to convert a level of voltage into the voltage or current required by the user through different forms of architecture. The input of the switching power supply is mostly AC power (such as city power) or DC power, and the output is mostly equipment that requires DC power, such as a personal computer, and the switching power supply performs the conversion of voltage and current between the two.