Refined switching power supply circuit principle

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Summary:

The circuit composition of the switching power supply:

The main circuit of the switching power supply is composed of an input electromagnetic interference filter (EMI), a rectification and filtering circuit, a power conversion circuit, a PWM controller circuit, and an output rectification and filtering circuit. The auxiliary circuit has an input over-voltage protection circuit, an output over-voltage protection circuit, an output over-current protection circuit, and an output short-circuit protection circuit.

The circuit block diagram of the switching power supply is as follows:

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