A Sub-Electron Readout Noise CMOS Image Sensor with Pixel-Level Open-Loop Voltage Amplification

📋 论文概要

本文提出了一种具有像素级开环电压放大的CMOS图像传感器，实现了亚电子读出噪声。通过光子转移曲线测量和噪声直方图分析，发现噪声性能受低频RTS噪声限制。

💡 主要创新点

• 提出像素级开环电压放大结构，替代传统源跟随器缓冲，实现亚电子读出噪声。
• 通过光子转移曲线和像素直方图分析，揭示了RTS噪声是限制性能的主要因素。

🏷 关键词

📄 原文摘要

CSEM, Zurich, Switzerland, 3 CSEM, Landquart, Switzerland, 4 EPFL, Neuchâtel, Switzerland The conversion factor used to calculate the equivalent noise charge is determined by a photon transfer curve measurement. Investigations of the pixel histogram of the readout noise as well as the measured amplitude distributions of selected pixels with noise values above average indicate that the observed noise performance is limited by low-frequency noise, particularly RTS noise [5]. 1 2 State-of-the-art low-noise CMOS image sensors use source-followers for pixellevel buffering of the sense node voltage. Due to the near-unity gain of such pixel-level circuits and the typical values of the column conductor’s load capacitance the thermal noise on the column conductor generated by the pixel-level source-follower reaches amplitudes that are far from single-electron resolution. Conventional image sensors reduce the bandwidth of the source-follower’s noise

👥 作者与机构

Christian Lotto1,2, Peter Seitz3,4, Thomas Baechler2

Heliotis, Root Längenbold, Switzerland,