Design of an Amplitude-Pulse Modulated Charge-Sensitive Analog Front End Circuit for SiC Neutron Detector
A four-channel readout application specific integrated circuit(ASIC)is developed in order to read the extremely weak output current pulse from SiC channel neutron detector.Each channel of the ASIC contains a charge-sensitive amplifier with high-gain and high-bandwidth,a high-order shaping circuit,and a peaking hold and time detection circuit.The proposed ASIC optimizes the CSA feedback loop,thus improving the gain linearity and avoiding the impact of leakage current inflow on the baseline.The circuit achieves the quick respond to the input signal and the extraction of energy and time information.The layout design of the AISC is based on the 0.18 μm CMOS process.The post simulated results show that the equivalent input charge range of the system is 1.14 fC～22.35 fC.The charge con-version gain reaches 71.19 mV/fC.Moreover,the nonlinear error decreases to less than 1.6％ and the equivalent noise charge is only 22 e-.The simulated results indicate that the ASIC has achieved high gain and high linearity.The ASIC can accurately reads out and am-plifies the neutron signal based on the characteristics of SiC channel neutron detector.
SiC neutron detectorcharge sensitive amplifierlow noise
万方数据
维普
