Device mismatch limitations on performance of a Hamming distance classifier

The performance of a memory based computational engine, a Hamming distance classifier that employs static memory cells and an analog Winner-Takes-All circuit depends on device matching in the various parts of the circuit. This dependence has been analyzed, leading to design criteria for choosing the device sizes and chip structure. The theoretical performance of a CMOS chip designed to operate in the subthreshold and transition region has been compared with the actual experimental results.