Patent ID: 7106129

Claim:
A semiconductor device, comprising: a differential amplifier for amplifying a difference between a first input potential and a second input potential, wherein said differential amplifier includes a first MOS transistor receiving a control potential at its gate, for determining a bias current of said differential amplifier according to said control potential, and second and third MOS transistors having a threshold voltage higher than that of said first MOS transistor and forming a pair for differential amplification; a load circuit; and a fourth MOS transistor connected between an externally applied first power supply potential node and said load circuit and having its gate potential controlled according to an output of said differential amplifier, for supplying a second power supply potential resulting from down-converting said first power supply potential to said load circuit, wherein said first input potential is a reference potential, and said second input potential is a function of said second power supply potential, wherein said load circuit includes a fifih MOS transistor having a gate oxide film thinner than gate oxide films of said second and third MOS transistors, and said first MOS transistor has a gate oxide film thinner than the gate oxide films of said second and third MOS transistors.