Mitsumi Electric Company Ltd.

Mitsumi Electric, Ltd.

Akihiro Terada

Yoichi Takano

Kohei Sakurai

Shinichiro Maki

Nagayoshi Dobashi

An output device includes an output transistor that outputs an output current, a first driver that drives the output transistor so that a feedback voltage of an output voltage of the output transistor is in agreement with a reference voltage, an RC circuit that has a capacitor connected to the ground and a resistor connected in series to the capacitor, and a second driver that drives the output transistor to increase the output current when a potential difference between ends of the resistor, generated by the feedback voltage supplied between ends of the RC circuit, is increased by a decrease of the output voltage.

Output device which supplies a current with improved transient response characteristic and reduced current consumption

A regulator includes a transistor connected between an input and an output. A feedback voltage controls the transistor to keep the output voltage constant. A first circuit functions as a comparator to compare a detection voltage from the output of the transistor and the feedback voltage when the output current is higher than a predetermined value, and functions as a buffer when the output current is lower than the predetermined value. A second circuit receives a reference voltage, the feedback voltage, and an output from the first circuit, and generates (i) a difference between the feedback voltage and the first circuit output when the reference voltage is lower than the first circuit output, and (ii) a difference voltage between the feedback voltage and the reference voltage when the reference voltage is higher than the first circuit output, and supplies a control voltage to control the output of the transistor.

Semiconductor integrated circuit for regulator

Disclosed is a low voltage detection circuit. The low voltage detection circuit includes, a voltage comparison circuit, an output stage, an electric current circuit, and a judgment circuit. When the voltage comparison circuit detects that the voltage of the detection target is a predetermined voltage value or less, an output state of the output stage is promptly changed. When the voltage comparison circuit detects that the voltage of the detection target is a predetermined voltage value or more, the output state of the output stage is changed after a delay time obtained by the electric current circuit.

Low voltage detection circuit

A differential amplifier circuit including: a differential input stage including a pair of differential MOS transistors, a pair of load elements, and a first constant-current source; an output stage including an output MOS transistor and a second constant-current source; a constant-current MOS transistor provided in parallel to one of the first and second constant-current sources; and a boost current controlling MOS transistor in which a potential of a connection node of the output MOS transistor and the second constant-current source is applied to a gate terminal thereof; wherein the boost current controlling MOS transistor is turned on when a voltage inputted to a gate terminal of one of the pair of differential MOS transistors changes, and a current of the constant-current MOS transistor is added to one of the first and second constant-current sources and is allowed to flow.

Differential amplifier circuit that can change current flowing through a constant-current source according to load variation, and series regulator including the same

A disclosed amplifier circuit is capable of changing a gain to amplify an input signal according to a control signal. The amplifier circuit comprises a differential amplifier circuit adapted to receive and amplify the input signal to output the amplified input signal as an output signal, a first resistance and one or more second resistances connected to the differential amplifier circuit and adapted to set the gain, and one or more gain control circuits adapted to change the gain by controlling one or more electrical couplings of the one or more second resistances according to the control signal.

Growing community of inventors

Tama, Japan

Akihiro Terada