It should be noted that the “switching power supply” we often say is actually the abbreviation of “high-frequency switching power supply”, which has nothing to do with the power supply itself.
In fact, the power supply of the end user’s PC adopts a more optimized solution: a closed loop system – the circuit responsible for controlling the switching tube, obtains a feedback signal from the output of the power supply, and then according to the power of the PC A transformer that is used to increase or decrease the frequency of the voltage within a certain period to accommodate the power supply (this method is called PWM, Pulse Width Modulation).