WORKSHOP PAPER
2.1µm LFM Automotive Pixel with Single Photodiode and 126 dB of Single Exposure Dynamic Range
Manuel Innocent, Pei Heng (Benjamin) Hung, Grady Anderson, Bartosz Banachowicz, Harshvardhan Jog, Gurvinder Singh, Bharat Balar, Anirudh Oberoi, Maheedhar Suryadevara

Abstract

This paper reports on work in progress on a 2.1 µm rolling shutter HDR pixel for automotive applications. We previously reported on an overflow pixel with a single exposure dynamic range (SE DR) of 110 dB and an SNR above 25 dB at each of the transition points up to 125°C [11]. This paper discusses extending the SE DR of this architecture to 126 dB (SNR1 based). To our knowledge this is the highest SE DR reported for a linear mode single PD pixel. At the pixel level the main improvement is an increase in the overflow capacitance. At the circuit level the focus is on reducing the read noise by increasing the analog gain, reducing the bandwidth and introducing correlated multiple sampling. With a second exposure the total dynamic range is up to 150 dB. This paper presents test chip results and discussion of the architectural choices.
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/es6a-7h7l
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Keywords

2.1µm, LFM Automotive Pixel, Single Photodiode, Dynamic Range,

References

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