Semiconductor device provided with regulator circuit having reduced layout area and improved phase margin

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;
• voltage divider resistance elements 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, that compensates a phase lag of an output signal from the transistor;
• wherein the voltage divider is formed of the electrode layer of the phase compensation capacitor that is closer to the semiconductor substrate, and wherein a parasitic capacitance between the voltage divider and the output terminal of the transistor compensates the phase lag.

A regulator comprising:

• a transistor having first and second electrodes coupled to a power supply terminal and an output terminal of the transistor, and having a gate terminal;
• first and second resistors formed in a surface of a semiconductor substrate and connected together in series as a voltage divider;
• a differential operational amplifier having a first input terminal coupled to a divided voltage output by the voltage divider and a second input terminal coupled to a reference voltage, and that provides a differential output responsive thereto;
• and
• a phase compensation capacitor formed over the voltage divider and including first and second electrode layers with an interlayer film formed therebetween, the first electrode layer being formed closer to the semiconductor substrate than the second electrode layer and being connected to the output terminal of the transistor.

A regulator formed on a semiconductor substrate, comprising:

• a transistor having first and second electrodes coupled to a power supply terminal and an output terminal of the transistor, and having a gate terminal;
• first and second resistors connected together in series as a voltage divider;
• a differential operational amplifier having a first input terminal coupled to a divided voltage output by the voltage divider and a second input terminal coupled to a reference voltage, and that provides a differential output responsive thereto;
• and
• a phase compensation capacitor including first and second electrode layers with an interlayer film formed therebetween,
• wherein the voltage divider is formed of the first electrode layer of the phase compensation capacitor which is closer to the semiconductor substrate than the second electrode layer.