A 140 dB Single-Exposure Dynamic-Range CMOS Image Sensor with In-Pixel DRAM Capacitor
Youngsun Oh, Lim Jungwook, Soeun Park, Dongsuk Yoo, Moosup Lim, Joongseok Park, Seojoo Kim, Minwook Jung, Sungkwan Kim, Junetaeg Lee, In-Gyu Baek, Kwangyul Ryu, Kyungmin Kim, Youngtae Jang, Min-Sun Keel, Gyu-Jin Bae, Seunghun Yoo, Youngkyun Jeong, Bumsuk Kim, JungChak Ahn, Haechang Lee, JoonSeo Yim
Abstract
This paper presents a CMOS image sensor with a $2.1\ \mu \mathrm{m}$ pixel for automotive applications. By using a sub-pixel structure and a high-capacity DRAM capacitor per pixel, a single exposure dynamic range achieves 140 dB at $85 ^{\circ}\mathrm{C}$, supporting LED flicker mitigation. Dual conversion gain circuits of a small photodiode enable SNR to stay above 23 dB at $105 ^{\circ}\mathrm{C}$ even with the very high capacitance. The full-depth deep trench isolation prevents electrical crosstalk between pixels even in extremely high illuminance conditions and achieves high conversion gain for low random noise of 0.83 e-.