Abstract: A voltage regulator permits reduced current consumption by promptly and timely stopping the operation of an inrush current protection circuit immediately after the voltage regulator is started up. The voltage regulator has an output voltage detection circuit, which issues a detection signal to actuate the inrush current protection circuit when a low voltage at an output terminal is detected at the time of starting up the voltage regulator. When it is detected that the voltage at the output terminal has reached a predetermined level, the operation of the inrush current protection circuit is stopped and a power path of the output voltage detection circuit is cut off.

Abstract: A voltage regulator has a phase compensation circuit which changes consumption current according to load current thereby to reduce consumption current. The phase compensation circuit includes: a first transistor having a drain connected to an output terminal of an error amplifier circuit; a second transistor having a drain connected to a gate of the first transistor and a gate connected to the gate of the first transistor; a current mirror circuit connected to the output terminal of the error amplifier circuit, a drain of the first transistor, and the drain of the second transistor; and a capacitor connected between the gate of the second transistor and a drain of an output transistor. Thereby, current consumed by the phase compensation circuit can be changed according to the load current, resulting in that the voltage regulator consumes less current.

Abstract: A voltage regulator permits reduced current consumption by promptly and timely stopping the operation of an inrush current protection circuit immediately after the voltage regulator is started up. The voltage regulator has an output voltage detection circuit, which issues a detection signal to actuate the inrush current protection circuit when a low voltage at an output terminal is detected at the time of starting up the voltage regulator. When it is detected that the voltage at the output terminal has reached a predetermined level, the operation of the inrush current protection circuit is stopped and a power path of the output voltage detection circuit is cut off.

Abstract: There is provided a voltage regulator capable of achieving a fast transient response upon activation without allowing an abnormal consumption current to flow. The voltage regulator of the present invention includes: a booster circuit for detecting output current from an output transistor and outputting a boost signal to a first differential amplifier circuit; a sensing transistor for sensing the output current; a first transistor for making an adjustment to enable the output current to be copied accurately; and a second differential amplifier circuit in which the output terminal is connected to the gate of the first transistor, the inverting input terminal is connected to the drain of the sensing transistor, and the non-inverting input terminal is connected to the output terminal.

Abstract: Provided is a voltage regulator including a phase compensation circuit capable of obtaining an accurate output voltage. The phase compensation circuit includes: a first constant current circuit connected to a gate of an output transistor; a first transistor having a drain connected to the gate of the output transistor; and a second transistor having a drain connected to a gate of the first transistor, a second constant current circuit, and a resistor and having a gate connected to the resistor and any one terminal of a first capacitor, the first capacitor having the other terminal connected to an output terminal of the voltage regulator. This configuration prevents a current from flowing from an output terminal of the differential amplifier circuit to the drain of the first transistor, to thereby reduce an offset voltage to be generated in input transistors of the differential amplifier circuit, thus obtaining an accurate output voltage.

Abstract: A voltage regulator permits reduced current consumption by promptly and timely stopping the operation of an inrush current protection circuit immediately after the voltage regulator is started up. The voltage regulator has an output voltage detection circuit, which issues a detection signal to actuate the inrush current protection circuit when a low voltage at an output terminal is detected at the time of starting up the voltage regulator. When it is detected that the voltage at the output terminal has reached a predetermined level, the operation of the inrush current protection circuit is stopped and a power path of the output voltage detection circuit is cut off.

Abstract: A voltage regulator is capable of continuously and smoothly preventing an inrush current independently of a startup characteristic of a reference voltage circuit. The voltage regulator is provided with an inrush current protection circuit composed of a constant-current circuit, a first transistor having the source thereof connected to the constant-current circuit and the gate thereof controlled by an output voltage detection circuit, a capacitor connected between the first transistor and the gate of an output transistor, a second transistor having the gate thereof connected to the drain of the first transistor and the source thereof connected to a power supply terminal, and a third transistor, which is connected between the second transistor and the output transistor and the gate of which is controlled by the output voltage detection circuit.

Abstract: A voltage regulator has a phase compensation circuit which changes consumption current according to load current thereby to reduce consumption current. The phase compensation circuit includes: a first transistor having a drain connected to an output terminal of an error amplifier circuit; a second transistor having a drain connected to a gate of the first transistor and a gate connected to the gate of the first transistor; a current mirror circuit connected to the output terminal of the error amplifier circuit, a drain of the first transistor, and the drain of the second transistor; and a capacitor connected between the gate of the second transistor and a drain of an output transistor. Thereby, current consumed by the phase compensation circuit can be changed according to the load current, resulting in that the voltage regulator consumes less current.

Abstract: A voltage regulator is capable of continuously and smoothly preventing an inrush current independently of a startup characteristic of a reference voltage circuit. The voltage regulator is provided with an inrush current protection circuit composed of a constant-current circuit, a first transistor having the source thereof connected to the constant-current circuit and the gate thereof controlled by an output voltage detection circuit, a capacitor connected between the first transistor and the gate of an output transistor, a second transistor having the gate thereof connected to the drain of the first transistor and the source thereof connected to a power supply terminal, and a third transistor, which is connected between the second transistor and the output transistor and the gate of which is controlled by the output voltage detection circuit.

Abstract: A voltage regulator permits reduced current consumption by promptly and timely stopping the operation of an inrush current protection circuit immediately after the voltage regulator is started up. The voltage regulator has an output voltage detection circuit, which issues a detection signal to actuate the inrush current protection circuit when a low voltage at an output terminal is detected at the time of starting up the voltage regulator. When it is detected that the voltage at the output terminal has reached a predetermined level, the operation of the inrush current protection circuit is stopped and a power path of the output voltage detection circuit is cut off.

Abstract: There is provided a voltage regulator capable of achieving a fast transient response upon activation without allowing an abnormal consumption current to flow. The voltage regulator of the present invention includes: a booster circuit for detecting output current from an output transistor and outputting a boost signal to a first differential amplifier circuit; a sensing transistor for sensing the output current; a first transistor for making an adjustment to enable the output current to be copied accurately; and a second differential amplifier circuit in which the output terminal is connected to the gate of the first transistor, the inverting input terminal is connected to the drain of the sensing transistor, and the non-inverting input terminal is connected to the output terminal.

Abstract: Provided is a voltage regulator including a phase compensation circuit capable of obtaining an accurate output voltage. The phase compensation circuit includes: a first constant current circuit connected to a gate of an output transistor; a first transistor having a drain connected to the gate of the output transistor; and a second transistor having a drain connected to a gate of the first transistor, a second constant current circuit, and a resistor and having a gate connected to the resistor and any one terminal of a first capacitor, the first capacitor having the other terminal connected to an output terminal of the voltage regulator. This configuration prevents a current from flowing from an output terminal of the differential amplifier circuit to the drain of the first transistor, to thereby reduce an offset voltage to be generated in input transistors of the differential amplifier circuit, thus obtaining an accurate output voltage.