Monostable-Bistable Transition Logic Elements: Threshold Logic vs. Boolean Logic Comparison

Threshold logic is an interesting alternative to Boolean logic in the field of high-performance arithmetic circuits. It offers reduced logic depth and gate count. A competitive implementation of threshold logic uses monostable-bistable transition logic elements (MOBILE). The aim of this contribution is to evaluate a specific implementation of MOBILE based on negative-differential-resistance (NDR) MOS structures. This implementation is compared as fairly as possible to Boolean-logic circuits. Simulations of majority-voting gates with 1 to 7 inputs are carried out using the same CMOS process for both logic styles. Results show the improvement brought by the MOBILE implementation regarding to area, power consumption and power-delay product, when the number of inputs becomes large.