Development Of SiPM High Voltage Power Supply For Nuclear Physics Experiment

Silicon Photomultiplier(Si PM)is a new generation of semiconductor photon detectors with good anti-magnetic properties and low cost,which are widely used in the fields of high energy physics,nuclear medicine imaging and nuclear physics.Because the gain of Si PM is closely related to the bias voltage and temperature of Si PM,and the current commercial power supply does not have the function of temperature correction,low integration,online control and high cost.In view of these problems,it is necessary to design a high-voltage power supply with adaptive temperature,high integration,low cost and online control.This paper will study from the following two aspects: one is to realize the design of high voltage power supply,the other is to build a set of electronics system for Si PM readout.Specific research contents are as follows:1.The overall design of the high voltage power supply and the design and function of each module were studied,including FPGA configuration circuit design,high voltage generation design,voltage detection design and temperature detection design.At the same time,the Ethernet module was designed to realize the on-line adjustable output voltage.This paper focuses on the hardware circuit design and software design of each module.Through schematic drawing and performance testing,the experimental results indicate that the integral non-linearity of the DC/DC module in the high-voltage power supply is 0.14‰;at different temperatures,the maximum rate of change in system gain is 1.12%;the maximum fluctuation of high voltage power supply is about 0.01 V,;the ripple coefficient of high voltage power supply is below 0.02%.Therefore,the high voltage power supply meets the characteristics of adaptive temperature,low ripple and high stability.2.In order to test the characteristics of high voltage power supply,set up a set of Si PM based readout electronics system.Bias voltage is provided to the Si PM by the high-voltage power supply to realize the signal conversion of the Si PM detector.The readout system will shape,amplify,sample and maintain the converted signal,and finally use the Root to conduct data analysis,and verify the performance of the high-voltage power supply according to the comparison of resolution.Test results show that using this design of high voltage power supply and commercial power supply to provide Si PM bias voltage,through comparative analysis,the resolution of the universal peak of high voltage power supply and commercial power supply is 7.84% and 9.88%respectively,so the performance of high voltage power supply is better than that of commercial power supply.