SMIC 180 nm宽温区电荷灵敏前置放大器芯片研究OA

Wide-bandgap detectors are characterized by high energy resolution,a wide operating temperature range,and strong radiation resistance.To leverage the advantages of wide-bandgap semiconductor detectors,a low-noise charge-sensitive preamplifier(CSA)suitable for a wide temperature range was designed.The design is based on the SMIC 180 nm process and consists of a core differential operational amplifier,a bandgap reference,and an output buffer.By optimizing the circuit structure of the operational amplifier and employing a fully symmetrical layout,a preamplifier with wide temperature range operation,low offset,and low noise is achieved.Post-simulation results indicate that the preamplifier can effectively detect sub-pC input charge signals within a rise time of 32 ns,with relative deviation of the amplification shall not exceed 1％.The circuit has an equivalent output impedance of 50 Ω,operates normally within the temperature range of-55 ℃ to 125 ℃,exhibits a sensitivity of 1.4 V·pC-1,and has a maximum single-particle charge detection capability of 0.4 pC and an equivalent noise charge of approximately 0.09 fC(600 e-).