There are many kinds of circuit structures of switching power supply:
(1) According to the driving mode, there are self-excited and separately-excited.
(2) According to the working mode of the DC/DC converter: ①Single-ended positive excitation type and reverse excitation type, push-pull type, half-bridge type, full-bridge type, etc.; ②buck type, boost type and buck-boost type, etc.
(3) According to the circuit composition, there are resonant type and non-resonant type.
(4) According to the control method: ①Pulse width modulation (PWM) type; ②Pulse frequency modulation (PFM) type; ③PWM and PFM hybrid type.
(5) According to whether the power supply is isolated and the feedback control signal coupling mode, there are isolation type, non-isolation type, transformer coupling type, photoelectric coupling type, etc.

The combination of the above methods can form a variety of switching-type regulated power supplies. Therefore, the designer needs to effectively combine the characteristics of various methods to produce a high-quality switching-type regulated power supply that meets the needs.