Voltage regulator having a phase compensation circuit
View Patent ↗A voltage regulator is equipped with the first and the second source-grounded amplifier circuits connected to an output terminal of a differential amplifier circuit; a phase compensation circuit having a resistor part and a capacitor part, and connected between an output terminal of the first source-grounded amplifier circuit and an output terminal of the second source-grounded amplifier circuit; and an output transistor connected to the output terminal of the second source-grounded amplifier circuit. At least one of the resistor part and the capacitor part of the phase compensation circuit has a filter.
1. A voltage regulator, comprising:
a differential amplifier circuit configured to amplify a difference between a reference voltage and a feedback voltage both provided to the differential amplifier circuit, and to supply an amplified difference;
a first source-grounded amplifier circuit connected to an output terminal of the differential amplifier circuit;
a second source-grounded amplifier circuit connected to the output terminal of the differential amplifier circuit;
a phase compensation circuit having a resistor part and a capacitor part, and connected between an output terminal of the first source-grounded amplifier circuit and an output terminal of the second source-grounded amplifier circuit; and
an output transistor connected to the output terminal of the second source-grounded amplifier circuit,
at least one of the resistor part and the capacitor part in the phase compensation circuit including a filter, and wherein the capacitor part includes a first capacitor and a second capacitor connected in parallel, and the filter comprises a low-pass filter connected in series to the second capacitor, the low pass filter comprising a resistor and a third capacitor having a terminal connected to ground.
2. The voltage regulator according to claim 1 , wherein the resistor part of the phase compensation circuit includes a first resistor and a second resistor connected in series, and a high-pass filter connected in parallel to the second resistor.
3. The voltage regulator according to claim 1 , wherein the resistor part of the phase compensation circuit includes a first resistor and a second resistor connected in parallel, and a high-pass filter connected in series to the second resistor.
4. A voltage regulator comprising:
a differential amplifier circuit configured to amplify a difference between a reference voltage and a feedback voltage both provided to the differential amplifier circuit, and to supply an amplified difference;
a first source-grounded amplifier circuit connected to an output terminal of the differential amplifier circuit;
a second source-grounded amplifier circuit connected to the output terminal of the differential amplifier circuit;
a phase compensation circuit having a resistor part and a capacitor part, and connected between an output terminal of the first source-grounded amplifier circuit and
an output terminal of the second source-grounded amplifier circuit; and
an output transistor connected to the output terminal of the second source-grounded amplifier circuit,
at least one of the resistor part and the capacitor part in the phase compensation circuit including a filter;
wherein the capacitor part of the phase compensation circuit includes a first capacitor and a second capacitor connected in parallel, and the filter comprises a low-pass filter connected in series to the second capacitor, the low pass filter comprising a resistor and a third capacitor having a terminal connected to ground.
5. A voltage regulator comprising:
a differential amplifier circuit configured to amplify a difference between a reference voltage and a feedback voltage both provided to the differential amplifier circuit, and to supply an amplified difference;
a first source-grounded amplifier circuit connected to an output terminal of the differential amplifier circuit;
a second source-grounded amplifier circuit connected to the output terminal of the differential amplifier circuit;
a phase compensation circuit having a resistor part and a capacitor part, and connected between an output terminal of the first source-grounded amplifier circuit and an output terminal of the second source-grounded amplifier circuit;
an output transistor connected to the output terminal of the second source-grounded amplifier circuit,
at least one of the resistor part and the capacitor part in the phase compensation circuit having a filter, and
wherein the resistor part of the phase compensation circuit includes a first resistor and a second resistor connected in parallel, and a low-pass filter connected in series to the second resistor.