In this paper, a bandgap voltage reference (BGR) with a low temperature coefficient, used for readout circuits of SPAD, has been designed and fabricated successfully in the standard MXIC 0.5µm 1P3M CMOS process. The area of the core circuit occupies 244×215µm2. The test results show that the designed bandgap reference could work normally under the power supply voltage of 2.8V to 8V with a line regulation (LNR) of 0.0096%. At room temperature (25°C), the stable reference output voltage is 1.168V. The reference voltage varies by only 1.8mV within the temperature range of 0~150°C, and leads to a temperature coefficient of 10.28ppm/°C. Under the power supply of 5V, the BGR chip exhibits a power supply rejection ratio (PSRR) of 76.4dB at 1KHz.
