Minipix: focal plane temporal frequency image processor

Previous research has highlighted the potential utility in analysing temporal frequency signatures. This paper introduces an improved algorithm capable of accurately encoding the fundamental frequency of such temporal signatures in the form of a robust pulse train, while consuming minimal power and area. The approach makes use of focal-plane computation techniques to produce a compact pixel-processor, consuming 60 μm by 60 μm when implemented in a 0.6 μm process, with a fill factor of 14.1%. The adopted analogue circuit techniques are biased in the subthreshold region of operation, giving a power consumption of less than 100 nW per pixel when operating at 1 kHz from a 5 V power supply.