CMOS 3-T digital pixel sensor with in-pixel shared comparator

A CMOS digital pixel sensor (DPS) VLSI architecture with in-pixel one-bit quantization is presented. A single column-parallel comparator is shared by all pixels in the column. This results in a compact 3-T pixel implementation. By eliminating the in-pixel source follower the pixel effective power dissipation is reduced by over two orders of magnitude compared to a conventional 3-T pixel. A 64×64 DPS test prototype with 10μm pixel pitch has been fabricated in 0.35μm standard CMOS and experimentally characterized.