A 640 × 640 Fully Dynamic CMOS Image Sensor for Always-On Operation

Injun Park, Woojin Jo, Chanmin Park, Byungchoul Park, Jimin Cheon, Youngcheol Chae

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

This article presents a 640 \times 640 fully dynamic CMOS image sensor for the always-on operation. It consists of a dynamic pixel source follower (SF), whose output signal is sampled into a parasitic column capacitor and then read out by a dynamic single-slope (SS) analog-To-digital converter (ADC) based on a dynamic bias comparator and an energy-efficient two-step counter. The prototype sensor was implemented in a 110-nm CMOS process, achieving 0.3% peak non-linearity, 6.1 e-rms random noise (RN), and 67-dB dynamic range. The power consumption is only 2.1 mW at 44 frames per second (fps) and is further reduced to 140 \mu \text{W} at 5 fps with the sub-sampled 320 \times 320 mode. This sensor achieves a state-of-The-Art energy efficiency figure-of-merit of 0.71 e- \cdot nJ.

Original language English 8944068 898-907 10 IEEE Journal of Solid-State Circuits 55 4 https://doi.org/10.1109/JSSC.2019.2959486 Published - 2020 Apr

All Science Journal Classification (ASJC) codes

• Electrical and Electronic Engineering