ULTRAFAST PIPELINED ADDERS USING RTTS

Ultrafast adders that perform 32 bit additions in less than 1 ns using resonant tunnelling transistors (RTTs) are proposed. Simulation results showing their subnanosecond performance are presented. The adders are shown to be better than others in terms of both area and speed. These results are obtained using true bistable logic which makes use of the bistability of circuits using the negative differential resistance (NDR) characteristic of the RTTs.