A 1.2mW CMOS temporal-difference image sensor for sensor networks

In this paper we report a 64×64 active pixel image sensor (APS), Mototrigger, which targets low-power image sensing for sensor networks. The image sensor computes the temporal-difference between two continuous light-intensity frames and communicates them in address-event format. The image sensor is capable of computing 30 temporal-difference frame/s and consumes 1.2mW with a 3V power supply. Light-intensity images are also available as an output at a speed of 60 frame/s. The pixel occupies an area of 29×28μm2 with a fill factor of 23%. The die size is 3mm by 3mm, including pads and test structures. The image sensor is fabricated in a 0.5μm bulk CMOS process.