An MTCMOS design methodology and its application to mobile computing

The multi-threshold CMOS (MTCMOS) technology provides a solution to the high performance and low power design requirements of modern designs. While the low V_th transistors are used to implement the desired function, the high V_th transistors are used to cut off the leakage current. In this paper, we (i) examine the effectiveness of the MTCMOS technology for Samsung´s 0.18 μm process, (ii) propose a new special flip-flop which keeps valid data during the sleep mode, and (iii) develop a methodology which takes into account the new design issues related to the MTCMOS technology. Towards validating the proposed technique, a personal digital assistant (PDA) processor has been implemented using the MTCMOS design methodology, and the 0.18 μm process. The fabricated PDA processor operates at 333 MHz, and consumes about 2 μW of leakage power. Whereas the performance of the MTCMOS implementation is the same as that of the generic CMOS implementation, three orders of reduction in the leakage power has been achieved.