On -vehicle overload protection circuit who has brush fan based on PWM control

The utility model relates to a circuit overload protection technical field, concretely relates to controls on -vehicle overload protection circuit and the protection method who has the brush fan based on PWM for one kind, and this protection circuit includes ON -OFF control circuit, amplifier circuit, power supply circuit, MOS drive shaping circuit and fan drive circuit, and ON -OFF control circuit, amplifier circuit, power supply circuit, MOS drive shaping circuit and fan drive circuit connect gradually, MOS drive shaping circuit is used for the voltage signal of voltage signal plastic for being fit for fan drive circuit with coming from amplifier circuit, the voltage signal that fan drive circuit is used for the utilization to come from MOS drive shaping circuit manages through MOS and drives the fan operation. The utility model discloses can effectively stop the stifled heavy current that changes or produce in the twinkling of an eye during the short circuit of fan burns out fan governor's drive MOS to red