Patent ID: 7994842

Claim:
A semiconductor integrated circuit apparatus, comprising: a first first main conductivity MIS transistor with a source connected to a first power supply; a second first main conductivity MIS transistor with a source connected to a drain of the first first main conductivity MIS transistor, a drain connected to a first current source, and a gate connected to a gate of the first first main conductivity MIS transistor and the first current source; a voltage amplifier that amplifies or attenuates a drain potential of the first first main conductivity MIS transistor to an arbitrary voltage up or down; and a leakage current detection first main conductivity MIS transistor that takes an output potential of the voltage amplifier as a gate potential, and has a substrate connected to a substrate of a first main conductivity MIS transistor of an internal circuit, wherein: the voltage amplifier satisfies the following equation when the drain potential of the first first main conductivity MIS transistor is amplified 3S volts up, I LLSI I LLCM = W LSI W LCM · W 1 W 2 · 1 10 3 where: S is a gate source voltage necessary to make a leakage current of the first main conductivity MIS transistor one digit higher or lower; I L.LSI is a leakage current of the first main conductivity MIS transistor of the internal circuit, I L.LCM is a leakage current of a leakage current detection first main conductivity MIS transistor T n1 , W LSI is a channel width of the first main conductivity MIS transistor of the internal circuit, W LCM is a channel width of the leakage current detection first main conductivity MIS transistor, W 1 is a channel width of the first first main conductivity MIS transistor, W 2 is a channel width of the second first main conductivity MIS transistor, and the first and second first main conductivity MIS transistor operate in a subthreshold region in such a manner that an absolute value of a difference in agate potential of the first first main conductivity MIS transistor and the second first main conductivity MIS transistor and the first power supply potential becomes equal to or smaller than a threshold voltage of the first and second first main conductivity MIS transistors.