In a power circuit which makes phase compensation by utilizing ESR of an output capacitor, a feedback signal based on an output voltage is supplied by a coupling capacitor to an N-channel MOS transistor on a saturated coupling side of a current mirror circuit inside an error amplification circuit.
1. A power circuit which compares a feedback signal based on an output voltage with a preset reference signal by an error amplifier to output a predetermined voltage, and
wherein the feedback signal is supplied to a transistor on a saturated coupling side of a current mirror circuit inside the error amplifier from a coupling capacitor.
2. The power circuit according to claim 1 , wherein the coupling capacitor is connected to the transistor on the saturated coupling side via a resistance.
3. The power circuit according to claim 1 , wherein a signal comprising a voltage converted from information on a current flowing in an output driver is used as the feedback signal.
4. The power circuit according to claim 1 , wherein the coupling capacitor is disposed separately from the transistor inside the error amplifier.
5. The power circuit according to claim 1 , wherein the drain and the gate of the transistor are short-circuited.
6. The power circuit according to claim 1 , wherein a terminal of the coupling capacitor is connected to the gate of the transistor.
7. The power circuit according to claim 1 , wherein the resistance includes a resistor with a first terminal and a second terminal, and that a terminal of the coupling capacitor is connected to the first terminal of the resistor, and the second terminal of the resistor is connected to the gate of the transistor.