Abstract
This thesis presents a low noise and high conversion gain readout IC with chopper stabilization technique for organic photoconductive film image sensor and a fixed biasing needed image sensor. To achieve a nice noise performance, the proposed capacitive trans-impedance amplifier (CTIA) with in-pixel correlated double sampling (CDS) cancels the offset of CTIA and suppresses the reset phase thermal noise which is induced by reset switch and OP. On the other hand, chopper stabilization technique is also applied to modulate flicker noise to the chopping frequency for the purpose of separating low frequency noise with low frequency signal. After that, signals are readout with multiple sampling by column-wise two-step dual-slope analog to digital converters. Finally, digital low-pass filter (LPF), which cut-off frequency is designed to be much lower than chopping frequency, is used to process the collection of data of each pixel to filter out thermal noise and modulated flicker noise. A prototype of 64×64 pixel imager employed these schemes has been designed and simulated in 0.18um 1P6M CMOS technology file with 3.3V supply voltage for both of analog and digital. The simulation results show that the proposed chopper stabilized CTIA ROIC achieves 99.9% linearity and improves SNR from 50.18dB to 53.05dB.