A low noise charge sensitive amplifier with adjustable leakage compensation in 0.18µm CMOS process

Gate leakage of charge sensitive amplifier (CSA) in deep submicron process not only increases noise but also impacts the DC voltage of preamplifier output. This paper proposes a CSA for CdZnTe particle detector readout implemented in 0.18µm CMOS process including its new reset and leakage compensation configuration which has low noise and short reset time, especially, is adjustable to fit leakage current variation. This design is tape out verified. The test chip achieves 250e equivalent noise charge. And its reset time is adjustable indeed.