A 0.5-V MTCMOS/SIMOX logic gate

Abstract

This paper proposes a multithreshold CMOS (MTCMOS) circuit that uses SIMOX process technology. This MTCMOS/SIMOX circuit combines fully depleted low-threshold CMOS logic gates and partially depleted high-threshold power-switch transistors. The low-threshold CMOS gates have a large noise margin for fluctuations in operating temperature in addition to high-speed operation at the low supply voltage of 0.5 V. The high-threshold power-switch transistor in which the body is connected to the gate through the reverse-diode makes it possible to obtain large channel conductance in the active mode without any increase of the leakage current in the sleep mode. The effectiveness of the MTCMOS/SIMOX circuit is confirmed by an evaluation of a gate-chain test element group (TEG) and an experimental 0.5-V, 40-MHz, 16-b ALU, which were designed and fabricated with 0.25-/spl mu/m MTCMOS/SIMOX technology.