Low-Power Techniques on a CMOS Vision Sensor Chip for Event Generation by Frame Differencing with High Dynamic Range

This paper addresses low-power design techniques on a CMOS vision chip working in global shutter mode for event generation by frame differencing with a per-pixel algorithm for high dynamic range (HDR). In particular, the paper focuses on the inclusion of the dynamic source follower (DSF) as buffer in exchange of the conventional source follower (CSF) in both the front-end sensor and the per-pixel processing circuits. The DSF mode cuts the power consumption in half with respect to that of the CSF approach with power gating techniques. These metrics are drawn from electrical simulations on a CMOS event pixel in 180 nm CIS technology.