Patent ID: 7633315

Claim:
A semiconductor integrated circuit device comprising: a power switch for cutting off power supply to a circuit block having a particular function; and a drive circuit for controlling said power switch, said drive circuit including a first transistor and a second transistor; wherein a drain electrode of said first transistor is electrically connected to a drain electrode of said second transistor; wherein a source electrode of said first transistor is electrically connected to a first potential power line supplied with a first potential; wherein a source electrode of said second transistor is electrically connected to a second potential power line supplied with a second potential; wherein said first transistor is a double gate transistor with a first gate and a second gate having a gate oxide film thickness larger than that of the said first gate; wherein the potentials on said first and second gates are controlled independently of each other; wherein in a first period, said second potential is supplied to said first gate of said first transistor to output said first potential from said drain electrode of said first transistor; and wherein, in a second period different from said first period, said first potential is supplied to said first gate of the first transistor and said second potential is supplied to said second gate of said first transistor to output said first potential from said drain electrode of said first transistor.