Semiconductor integrated circuit

Abstract

A high-threshold first conductivity transistor and a low-threshold second conductivity transistor are series-connected between a first actual power source line to the supplied with a power source voltage and a virtual power source line connected to the power source terminal of a circuit block constituted of a low-threshold transistor. The first and second conductivity transistors have reverse polarities. A power source control circuit switches on the first and second conductivity transistors while the circuit block works, and switches off them while the circuit block does not work. The series connection of the low-threshold second conductivity transistor to the high-threshold first conductivity transistor maximizes an increase in the on-resistance of the first and second conductivity transistors and increases the off resistance. Thus, the subthreshold current of the first and second conductivity transistors is suppressed. As a result, the power consumption of the standby period of the semiconductor integrated circuit is cut down.

Description

technical field [0001] The present invention relates to a semiconductor integrated circuit having a circuit block composed of low-threshold transistors, wherein the power supply voltage supplied to the circuit block is interrupted when the integrated circuit is not in operation. Background technique [0002] As the structure of semiconductor components becomes more refined, the power supply voltage provided to semiconductor integrated circuits also decreases year by year. As the power supply voltage becomes lower and the difference between the power supply voltage and the threshold voltage of the transistor becomes smaller, it becomes more difficult to turn on the transistor while its operating speed decreases. In order to prevent the above-mentioned problems, the threshold voltage of the transistor exhibits a tendency to decrease in synchronization with the power supply voltage. [0003] In addition, with the microfabrication of transistors, the leakage current (subthresho...

AI Technical Summary

Problems solved by technology

[0005] However, when the integration level of semiconductor integrated circuits increases with the microfabrication of semiconductor element structures, power consumption cannot be sufficiently reduced even with MTCMOS technology due to the subthreshold current of switching transistors.

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