Voltage regulator

1. A voltage regulator comprising:

an amplifier that amplifies a difference between a reference voltage and a voltage proportional to an output voltage;

an output MOS transistor that has a control terminal connected to an output terminal of said amplifier and that drops a power supply voltage to output an output voltage;

a first capacitive element that has a first terminal connected to said output terminal of said amplifier and a second terminal connected to ground or an output terminal of said output MOS transistor;

a second capacitive element that has a first terminal connected to said output terminal of said amplifier;

a control circuit that, subsequent to supply of said power supply voltage, controls operation activation of said amplifier and also supplies a drive signal to a second terminal of said second capacitive element; and

i-th capacitive element(s) (i=3 to n, with n being an integer of at least 3) having a first terminal connected to an output terminal of said amplifier; wherein

said control circuit, after operation activation of said amplifier, supplies drive signals, each of different timing, to a second to n-th of said capacitive elements, respectively.

2. The voltage regulator according to claim 1 , wherein said control circuit supplies drive signals selectively to the second to n-th of said capacitive elements respectively.

3. The voltage regulator according to claim 1 , wherein a ratio between a total capacitance of the second to n-th of said capacitive elements having said drive signals activated, and capacitance of said first capacitive element, is set based on the voltage of said output terminal of said amplifier in a steady state.

4. The voltage regulator according to claim 1 , wherein the first to n-th of said capacitive elements have a function of phase compensation with regard to amplification operation by said amplifier and said output MOS transistor.

5. The voltage regulator according to claim 1 , wherein, by said control circuit supplying a drive signal to second terminals of each of the second to n-th of said capacitive elements, the second to n-th of said capacitive elements are charged and each discharged at different timing.

6. The voltage regulator according to claim 5 , comprising

a resistance element; wherein

said control circuit discharges at least one of the second to n-th of said capacitive elements via said resistance element.

7. The voltage regulator according to claim 2 , wherein, by said control circuit supplying a drive signal to second terminals of each of the second to n-th of said capacitive elements, the second to n-th of said capacitive elements are charged and each discharged at different timing.

8. The voltage regulator according to claim 7 , comprising

a resistance element; wherein

said control circuit discharges at least one of the second to n-th of said capacitive elements via said resistance element.

9. A voltage regulator comprising:

an amplifier that amplifies a difference between a reference voltage and a voltage proportional to an output voltage;

an output transistor that includes a control terminal connected to an output terminal of the amplifier and that drops a power supply voltage to output the output voltage;

a controller that is free from connecting to an output terminal of the output transistor, the output terminal of the output transistor outputting the output voltage;

a first capacitor that is connected to the output terminal of the amplifier; and

a second capacitor that is connected between the output terminal of the amplifier and the controller,

wherein the controller controls operation activation of the amplifier, and supplies a drive signal to the second capacitor,

wherein the drive signal comprises a first drive signal,

wherein the voltage regulator further comprises:

a third capacitor that is connected between the output terminal of the amplifier and the controller,

wherein the controller supplies a second drive signal different from the first drive signal to the third capacitor.