Ultralow-voltage MTCMOS/SOI technology for batteryless mobile system

This paper describes an ultralow-power multi-threshold (MT) CMOS/SOI circuit technique that mainly uses fully-depleted MOSFETs. The MTCMOS/SOI circuit, which combines fully-depleted low- and medium-Vth CMOS/SOI logic gates and high-Vth power-switch transistors, makes it possible to lower the supply voltage to 0.5 V and reduce the power dissipation of LSIs to the 1-mW level. The validity of using the ultralow-voltage MTCMOS/SOI circuits is confirmed by the demonstration of two types of self-powered short-range wireless systems. One is a 300-MHz-band RF data transmission system. The other is an optical-wireless transmission system with white-colored-LED illumination. A 1-V SAW oscillator and a switched-capacitor-type DC-DC converter in the transmitter make possible self-powered RF transmission by the heat from a hand. An instantaneously-activated 0.5-V CPU in the receiver also makes self-powered operation under illumination possible.