Patent ID: 8773195

Claim:
A semiconductor device comprising: a buffer circuit that generates a power-supply voltage of a complementary field effect transistor circuit including a first field effect transistor of a first conductivity type and a second field effect transistor of a second conductivity type; a first replica transistor that is a replica of the first field effect transistor, the first replica transistor being diode-connected; a second replica transistor that is a replica of the second field effect transistor, the second replica transistor being diode-connected and being connected in parallel to the first replica transistor to share an anode and a cathode; and a voltage control circuit that controls a voltage between the anode and cathode shared by the first and second replica transistors in such a manner that a total current value of currents flowing in the first and second replica transistors becomes equal to a predetermined first target value, wherein the buffer circuit generates the power-supply voltage, with a target voltage being the voltage between the anode and cathode controlled by the voltage control circuit.