Temporal Noise Analysis and Reduction Method in CMOS Image Sensor Readout Circuit
Temporal Noise Analysis and Reduction Method in CMOS Image Sensor Readout Circuit
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DOI：
10.1109/ted.2009.2030619
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发表时间：
2009-09
影响因子：
3.1
通讯作者：
Bong Chan Kim;J. Jeon;Hyungcheol Shin
中科院分区：
文献类型：
--
作者：
Bong Chan Kim;J. Jeon;Hyungcheol Shin
分析了CMOS图像读出电路中的热噪声和低频噪声等时域噪声。此外，还考虑了相关双采样操作对噪声的影响。我们推导出了特定读出电路的解析噪声方程，并通过与模拟结果的比较，证实了其有效性。热噪声模型是准确的短沟道器件工作在饱和区。由于读出电路的像素内器件（源极跟随器和选择晶体管）的尺寸相对较小，并且因此呈现随机电报信号（RTS）噪声，因此1/f和RTS噪声都被考虑用于它们的LF噪声。在分析噪声成分的基础上，提出了通过调整读出电路中晶体管尺寸来降低噪声的方法。
Temporal noise such as thermal and low-frequency noise (LF noise) in the CMOS imager readout circuit has been analyzed. In addition, the effect of correlated double sampling operation on the noise was included. We have derived an analytical noise equation for the specified readout circuit, and confirmed its validity by comparing it with the simulation result. Thermal noise model which is accurate in short-channel devices operating in saturation region was used. Since the in-pixel devices (source follower and selection transistor) of the readout circuit are relatively small in size, and thus exhibits random telegraph signal (RTS) noise, both 1/f and RTS noise were considered for their LF noise. Based on the analyzed noise components, we presented the noise reduction method by adjusting the transistors sizes in the readout circuit.