A Low-power, Low-Noise Readout ASIC for Gamma-ray Dosimeter Based on CdZnTe Detector

In order to meet the design requirements of portal dosimeters based on Cadmium zinc telluride (CdZnTe) detector, a low power and low noise readout ASIC is proposed in this paper. The power consumption is decreased while the equivalent noise charge (ENC) is not seriously degraded by carefully optimizing the bias current of charge sensitive amplifier. The chip area is 0.127 mm
²
excluding the bias and bandgap circuit. The power consumption of the chip is 1.518 mW at the supply voltage of 3.3 V. The simulated equivalent noise charge(ENC) is about 213.3 e
^-
. The simulation results show that the non-linear error is 6.32% when the particle energy ranges from 30 keV to 1.5 MeV.