Article ID: 21.20240392
The paper presents a high linearity and wide dynamic range readout integrated circuit (ROIC) for four-quadrant detector (4QD) in position sensitive detection applications. A capacitive transimpedance amplifier (CTIA) was adopted as the basic building block, and a saturation monitoring technique using a comparator and a current mirror (CM) was proposed to adaptively regulate the input photocurrent. The designed readout circuit is fabricated in TSMC 0.18 μm 3.3 V CMOS process. The simulation results show that the dynamic ranges of proposed ROIC equipped with 5: 1 and 2: 1 CM are 101.8 dB and 93.9 dB, respectively. The measurement results demonstrate that an output linearity greater than 99%, and a dynamic range of 85.2 dB can be achieved for the proposed ROIC with a 2: 1 CM, and 5.9 dB improvement was realized compared to the conventional CTIA.
