Multiple-valued source-coupled logic VLSI based on adaptive threshold control and its applications

A new multiple-valued current-mode (MVCM) integrated circuit, based on adaptive threshold voltage control (ATVC) is proposed for high-speed VLSI applications, while maintaining low power. Adaptive threshold voltages, which are changed in the opposite direction to an input signal, are generated so that the voltage difference between an input voltage and a threshold voltage is always larger than that of a fixed threshold voltage control (FTVC). Moreover shifting of an input to a lower voltage results in better performance. As a typical application of a high-performance arithmetic circuit, a radix-2 signed-digit full adder (SDFA) is designed in a 0.18-/spl mu/m CMOS technology. Simulation results show that the speed of the SDFA, based on the proposed ATVC, is almost 1.7 times faster than that of conventional FTVC under normalized power consumption.