APD reverse-bias voltage control circuit based on double closed-loops

The utility model discloses an APD reverse-bias voltage control circuit based on double closed-loops. The circuit comprises a control circuit body, a reverse-bias voltage supplying circuit, a current mirror image circuit and a feedback circuit. The input end of the reverse-bias voltage supplying circuit is connected with the control circuit body. Voltage output by the reverse-bias voltage supplying circuit is loaded on an APD through the current mirror image circuit. The feedback circuit feeds the reverse-bias voltage back to the control circuit body. The control circuit body adjusts the voltage and outputs the voltage to the reverse-bias voltage supplying circuit according to the voltage output by the feedback circuit. Due to the fact that the first feedback circuit is adopted, integrated closed-loop control is formed. Therefore, the control circuit body can adjust the output control voltage and stability and accuracy of the reverse bias voltage on the APD are guaranteed.