Light-emitting diode (LED) constant current driving circuit

The invention discloses a light-emitting diode (LED) constant current driving circuit which comprises an alternating current input power supply, a rectification circuit and a constant current control circuit, wherein the rectification circuit is used for receiving the alternating current input power supply and rectifying the alternating current input power supply to obtain a direct current voltage, the constant current control circuit is connected in series with a load and comprises a power switching tube, an output current is adjusted by controlling on and off states of the power switching tube so as to lead the average current passing through the load to keep constant, and a voltage division capacitor is connected in series between the alternating input power supply and the rectification circuit. By connecting the voltage division capacitor in series to an input end, drop voltage at the two ends of the voltage division capacitor is maximum when the power switching tube is switched on, a voltage division effect is achieved, thus, the drop voltage of the power switching tube during switching on is reduced, the switching-on loss of the power switching tube is reduced, and the working efficiency of the circuit is improved.