Patent ID: 6856123

Claim:
A semiconductor device provided with a regulator circuit formed on a semiconductor substrate, comprising: a transistor having a source and a drain, either of which is connected to a power supply terminal and an other of which is connected to an output terminal of the transistor; a voltage divider comprising a first voltage divider resistor element and a second voltage divider resistor element connected together in series between a ground terminal and the output terminal of the transistor; a differential operational amplifier element that differentially amplifies a reference voltage inputted to an inverting input terminal thereof, and a voltage divided by the voltage divider inputted to a non-inverting input terminal thereof, and that supplies the amplified voltages to a gate of the transistor, to thereby control an output voltage of the transistor; and a phase compensation capacitor formed of an interlayer film between electrode layers and overlaid two-dimensionally on the voltage divider, wherein the electrode layer closer to the semiconductor substrate is connected to the output terminal of the transistor, and a parasitic capacitance between the output terminal of the transistor and the voltage divider compensates a phase lag of an output signal from the transistor.