POWER SUPPLY CIRCUIT FOR RADIATION DETECTOR AND SEMICONDUCTOR RADIATION DETECTOR USING THE SAME

PROBLEM TO BE SOLVED: To provide a power supply circuit for a radiation detector, which immediately recovers voltage to be applied to the detector after refresh and is compatible with a high-voltage power supply device that is inexpensive and provides a small current.SOLUTION: A power supply circuit for a radiation detector, which applies a bias voltage to the radiation detector, comprises: a buffer capacitor that is connected in parallel to the output of a high-voltage power supply device and accumulates electrical charges; and a voltage regulator circuit that inputs power from the buffer capacitor, converts it to a predetermined voltage and maintains it by adjustment, and outputs power of the predetermined voltage to a refresh control circuit that refreshes the radiation detector at predetermined cycles. The voltage regulator circuit charges the radiation detector by utilizing the electric charges accumulated by the buffer capacitor in a voltage recovery period when the refresh control circuit turns off the application of the bias voltage of the voltage regulator circuit to the radiation detector and turns on it again. The buffer capacitor is recovered to the predetermined voltage and charged in the voltage recovery period.