A 240-frames/s 2.1-Mpixel CMOS Image Sensor With Column-Shared Cyclic ADCs

作者：Lim Seunghyun^*; Cheon Jimin; Chae Youngcheol; Jung Wunki; Lee Dong Hun; Kwon Minho; Yoo Kwisung; Ham Seogheon; Han Gunhee

来源：IEEE Journal of Solid-State Circuits, 2011, 46(9): 2073-2083.

DOI：10.1109/JSSC.2011.2144010

• CMOS image sensor
• column-parallel ADC
• cyclic ADC
• single-slope conversion
• successive approximation

This paper proposes a low-power 240 frames/s 2.1 M-pixel CMOS image sensor with column-shared cyclic (CY) ADCs. Two-column shared CY-ADC architecture and two-level stacked ADC placement are employed for low-power and small pixel pitch design. The proposed CY-ADC uses only one OTA and four capacitors. Distributed clocking scheme using cascaded repeaters is proposed to reduce the required peak current. The prototype sensor was fabricated in a 0.13-mu m 1P4M process with pixel pitch of 2.25 mu m. The designed 10-bit ADC dissipates only 90 mu W/channel with 1.5 V supply. The measured DNL and INL are +0.59/-0.83 LSB and +2.8/-3.6 LSB, respectively. The measured maximum pixel rate is 500 Mpixels/s with total power consumption of 300 mW.

• 出版日期2011-9