Rohm Co., Ltd.

Takeshi Nagata

Yuhei Yamaguchi

Isao Takobe

Tetsuo Tateishi

Hironori Sumitomo

A linear power supply circuit according to the present invention is provided with: an output transistor provided between an input end to which an input voltage is applied and an output end to which an output voltage is applied; and a driver for driving the output transistor on the basis of the difference between a voltage based on the output voltage and a reference voltage. The driver is provided with: a differential amplifier for outputting a voltage according to the difference between the voltage based on the output voltage and the reference voltage; a capacitor one end of which has an output of the differential amplifier applied thereto and the other end of which has the voltage based on the output voltage applied thereto; a converter for converting a voltage based on the output of the differential amplifier into an electrical current and outputting the electrical current; and an electrical current amplifier for amplifying the electrical current of the output of the converter. The supply voltage of the differential amplifier is a first constant voltage or the input voltage.

Linear power supply circuit

A linear power supply circuit includes: an output stage including a first output transistor and a second output transistor, which are provided between an input terminal to which an input voltage is able to be applied and an output terminal to which an output voltage is able to be applied and are connected in parallel to each other; a driver configured to drive the first output transistor and the second output transistor based on a difference between a voltage based on the output voltage and a reference voltage; a resistor inserted between a gate of the first output transistor and a gate of the second output transistor; a capacitor having one end connected to the input terminal and the other end connected to a connection node between the resistor and the gate of the second output transistor; and a clamp element connected in parallel to the resistor.

Linear power supply circuit with phase compensation circuit

A linear power supply circuit, includes: output transistor between input terminal where input voltage is applied and output terminal where output voltage is applied; a driver driving the output transistor based on difference between voltage based on the output voltage and reference voltage; and phase compensation circuit, wherein the driver includes differential amplifier outputting voltage corresponding to the difference between the voltage based on the output voltage and the reference voltage, a first capacitance having one end where output of the differential amplifier is applied and the other end where ground potential is applied, a converter converting the voltage based on the output of the differential amplifier into current, and a current amplifier amplifying the current output from the converter, and wherein the phase compensation circuit lowers gain of transfer function of the linear power supply circuit and output capacitor connected to the output terminal.

A linear power supply circuit is provided with: an output transistor; and a driver for driving the output transistor on the basis of the difference between a voltage based on an output voltage and a reference voltage. The driver is provided with: a differential amplifier for outputting a voltage according to the difference between the voltage based on the output voltage and the reference voltage; a capacitor one end of which has an output of the differential amplifier applied thereto and the other end of which has the voltage based on the output voltage applied thereto; a converter for converting a voltage based on the output of the differential amplifier into an electrical current and outputting the electrical current; and a current amplifier for amplifying the electrical current of the output of the converter. The supply voltage of the differential amplifier is a first constant voltage or the input voltage.

A leak current absorption circuit for absorbing a leak current from an output transistor includes a switch connected to a grounding node on one end, a constant voltage circuit connected between the other end of the switch and an output node, a switch-operating circuit connected between the output node and the grounding node to operate the switch based on a voltage of the output node. When the voltage of the output node becomes equal to a predetermined threshold voltage or more, the switch-operating circuit turns on the switch to clamp the voltage of the output node by allowing at least a portion of the leak current from the output transistor flow to the grounding node.

Leak current absorption circuit, voltage generating circuit, power supply apparatus, and vehicle

There is provided a reference current generation circuit, including a reference voltage generation unit configured to generate a reference voltage by using a depression type transistor, and a voltage/current conversion unit configured to generate a reference current from the reference voltage.

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Kyoto, Japan

Takeshi Nagata