| 摘要 |
PROBLEM TO BE SOLVED: To suppress deterioration in the characteristics of a voltage regulator caused by changes of an operation environment.SOLUTION: According to one embodiment, a voltage regulator comprises an output transistor, a voltage dividing circuit, an error amplifier, a detection circuit, and a phase compensation capacitance circuit. The output transistor has one end to which a power source voltage is supplied, a control terminal to which a control signal is supplied, and the other end from which an output voltage is output. The voltage dividing circuit is connected between the other end of the output transistor and a reference power supply voltage, and outputs the divided voltage being a voltage obtained by dividing the output voltage. In the error amplifier, the divided voltage is supplied to a first input terminal, a reference voltage is supplied to a second input terminal, and the amplifier outputs the control signal corresponding to a difference between the divided voltage and the reference voltage. The detection circuit detects an operation environment. The phase compensation capacitance circuit adjusts phase compensation capacitance between the other end of the output transistor and the first input terminal of the error amplifier corresponding to the operation environment detected by the detection circuit. |
