Capacitance pen and charging circuit thereof

The utility model provides a capacitance pen charging circuit which comprises a switching circuit, a temperature detection circuit and a master control circuit. A USB interface; the detection end of the temperature detection circuit is arranged corresponding to the position of the USB interface, and the output end of the temperature detection circuit is electrically connected with the input end of the main control circuit; the input end of the switching circuit is electrically connected with the USB interface, and the controlled end of the switching circuit is electrically connected with the main control circuit; the output end of the switching circuit is grounded; the switching circuit is used for connecting/disconnecting a path between the USB interface and the ground; the temperature detection circuit is used for detecting the temperature of the USB interface and outputting a corresponding temperature detection signal; and the main control circuit is used for controlling the switch circuit to be switched o