Spike timing dependent plasticity (STDP) can ameliorate process variations in neuromorphic VLSI

A transient-detecting very large scale integration (VLSI) pixel is described, suitable for use in a visual-processing, depth-recovery algorithm based upon spike timing. A small array of pixels is coupled to an adaptive system, based upon spike timing dependent plasticity (STDP), that aims to reduce the effect of VLSI process variations on the algorithm´s performance. Results from 0.35 μm CMOS temporal differentiating pixels and STDP circuits show that the system is capable of adapting to substantially reduce the effects of process variations without interrupting the algorithm´s natural processes. The concept is generic to all spike timing driven processing algorithms in a VLSI.