WORKSHOP PAPER
Random Noise Improvement for Pixel-Parallel Single-Slope ADC
Masayuki Uno1, Kwuang-Han Chang2, Tsung-Hsun Tsai3, Toshiyuki Isozaki1, Rimon Ikeno1, Kazuya Mori1, Ken Miyauchi1, Yi-Hsuan Lin2, Sheng-Yeh Lai2, Chih-Hao Lin2, Wei-Fan Chou2, Junichi Nakamura1, Guang Yang2, Song Chen3, Chiao Liu3
1Brillnics Japan Inc., Tokyo, Japan
2Brillnics Inc., Hsinchu, Taiwan
3Reality Labs, Meta Platforms Inc., Redmond, WA, USA

Abstract

Low random noise (RN) design for pixel-parallel single-slope ADC (SS-ADC) in digital pixel sensor (DPS) is reported. The AC-based RN estimation with respect to the comparator bias current and bandwidth-limiting capacitor in DPS is discussed. RN is composed of thermal noise (TN) and flicker noise (FN), and FN easily becomes the major contributor in DPS. Low RN design comparable to that in digital correlated double sampling (D-CDS) scheme is considered after studying FN characteristics modulated by CDS...
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/su6t-7txr
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Keywords

pixel-parallel, single-slope ADC, random noise, digital pixel sensor, AC-based RN estimation, thermal noise, flicker noise, digital correlated double sampling, D-CDS, low noise design, pixel size, comparator bias current, bandwidth-limiting capacitor, low noise characteristics, small pixel, RN reduction, single-ended comparator, high gain, dynamic range, dual quantization operation, pixel-parallel architecture,

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