Variable-pitch driver, power supply and anti-reverse circuit of variable-pitch driver

The utility model provides a variable pitch driver, a power supply and an anti-reverse circuit thereof, the anti-reverse circuit adopts a second switch tube to replace an anti-reverse diode in the prior art, and is arranged in an output end positive pole transmission branch of a power supply module in the power supply; when the output end voltage of the second switch tube is smaller than the input end voltage, namely the output voltage of the power supply module, the second switch tube is controlled to be conducted; when the output end voltage of the second switch tube is greater than the input end voltage, namely greater than the output voltage of the power supply module, the high-potential end voltage of the clamping device is correspondingly increased, so that the first switch tube is switched on, and the control end voltage of the second switch tube is lowered and cannot be switched on; therefore, the electric energy of the output end of the second switch tube can be prevented from being reversely transmi