A 33uW 64x64 Pixel Vision Sensor Embedding Robust Dynamic Background Subtraction for Event Detection and Scene Interpretation

A6464-pixel ultra-low power vision sensor is pre-sented, performing pixel-level dynamic background subtraction asthe low-level processing layer of an algorithm for scene interpre-tation. The pixel embeds two digitally-programmable Switched-Capacitors Low-Pass Filters (SC-LPF) and two clocked compara-tors, aimed at detecting any anomalous behavior of the currentphoto-generated signal with respect to its past history. The 45 T,26m square pixel has afill-factor of 12%. The vision sensor hasbeen fabricated in a 0.35m 2P3M CMOS process, powered with3.3 V, and consumes 33W at 13 fps, which corresponds to 620pW/frame.pixel.