WORKSHOP PAPER
A CMOS Image Sensor with Pixelwise Triple-CG Modulation and Gain-Regulating Pre-ISP for Single-Frame Adaptive TCG-HDR Imaging
Yi Luo1, Shahriar Mirabbasi2
1Department of Component Development, vivo Mobile Communication Co., Ltd., Shenzhen, China
2Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada

Abstract

High dynamic range (HDR) imaging is a must-have feature in flagship mobile CMOS image sensors (CISs). Recently, pixels with triple conversion gains (CGs) are unveiled to enable triple-CG (TCG) HDR imaging. In this paper, we present a CIS design with on-chip CG modulator (CGM) and a dedicated image signal processor (pre-ISP) for adaptive TCG-HDR imaging. The CGM module containing pixel CG selection (CGS) blocks is in charge of pixel’s CG determinations and producing pixel CGS data. Pixels receive CG-mode signals and perform a single full-bit-depth readout with their own CGs. Both the pixel CGS data and the full-bit-depth image data are collected by the pre-ISP to produce HDR images. A prototype CIS chip consists of 640 × 320 TCG pixels has achieved a dynamic range of 89dB when applying adaptive TCG-HDR imaging. At a frame rate of 60fps, the power consumed in adaptive TCG-HDR imaging is 54% less than that in conventional TCG-HDR imaging. The presented CIS design and adaptive TCG-HDR imaging aim at low-power single-frame HDR imaging related applications in mobile cameras.
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/dyt6-ngar
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Keywords

CMOS Image Sensor, Triple-CG Modulation, TCG-HDR Imaging, CIS Design, Adaptive TCG-HDR Imaging,

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