A 381 fs/bit, 51.7 nW/bit nearest hamming-distance search circuit in 65 nm CMOS

The developed fully-parallel associative memory in 65nm CMOS for nearest Hamming-distance search is based on distance-frequency mapping with ring oscillators. The largest reference-data capacity of 128 pattern with 512 bit each, the shortest minimum search time of 3.81·10⁻¹³ s/bit and the lowest power dissipation of 5.17·10⁻⁸ W/bit in comparison to previous designs are reported. In particular, the power-delay product of 1.97·10⁻²⁰ J/bit is improved by a factor 140.