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US 11,892,481 B2Granted
Current detecting circuit and switching circuit
AssigneeMitsumi Electric Co., Ltd.
InventorsYoichi Takano, Kohei Sakurai
Life of this patent
Estimating the term…
Abstract
A current detecting circuit includes a first switching element, a second switching element, and a third switching element electrically coupled in series with the first switching element. An output side of the third switching element is electrically coupled to an output terminal. The current detecting circuit includes a current amplifier configured to detect a difference between a first output voltage of the first switching element and a second output voltage of the second switching element. The current amplifier outputs a relative current to be used for detecting an output current that flows out from the output terminal. A ratio of resistance associated with the first switching element to resistance associated with the second switching element is n:1.
Claims19
A current detecting circuit comprising:
- a power supply terminal;
- an output terminal;
- a first switching circuit of which an input side is electrically coupled to the power supply terminal, the first switching circuit including a first control terminal;
- a second switching circuit of which an input side is electrically coupled to the power supply terminal, the second switching circuit including a second control terminal electrically coupled to the first control terminal of the first switching circuit;
- a third switching circuit electrically coupled in series with the first switching circuit, an output side of the third switching circuit being electrically coupled to the output terminal;
- a first anti-backflow circuit electrically coupled in antiparallel with the first switching circuit to prevent backflow from the output terminal into the power supply terminal;
- a second anti-backflow circuit electrically coupled in antiparallel with the second switching circuit to prevent backflow into the power supply terminal;
- and
- a current amplifier configured to detect a difference between a first output voltage of the first switching circuit and a second output voltage of the second switching circuit, and to output a relative current to be used for detecting an output current that flows out from the output terminal,
- wherein a ratio of resistance associated with the first switching circuit to resistance associated with the second switching circuit is n:1, where n is an integer greater than one.
7 more elements
A semiconductor integrated circuit comprising:
- a power supply terminal;
- a first output terminal configured to be externally coupled to a load and via which an output current is configured to be output;
- a second output terminal;
- a control circuit;
- a first switching circuit of which an input side is electrically coupled to the power supply terminal, the first switching circuit including a first control terminal;
- a second switching circuit of which an input side is electrically coupled to the power supply terminal, the second switching circuit including a second control terminal electrically coupled to the first control terminal of the first switching circuit;
- a third switching circuit electrically coupled in series with the first switching circuit, an output side of the third switching circuit being electrically coupled to the output terminal;
- and
- a current amplifier configured to:
- detect a difference between a first output voltage of the first switching circuit and a second output voltage of the second switching circuit,
- generate a relative current proportional to the output current such that a magnitude of the relative current is lower than the output current, and
- output the relative current to the second output terminal,
- wherein the control circuit is configured to turn on the first switching circuit and the third switching circuit, so that the power supply terminal and the first output terminal become conductive.
10 more elements
A semiconductor integrated circuit comprising:
- a power supply terminal;
- a first output terminal configured to be externally coupled to a load and via which an output current is configured to be output;
- a second output terminal;
- a control circuit;
- a first switching circuit of which an input side is electrically coupled to the power supply terminal, the first switching circuit including a first control terminal;
- a second switching circuit of which an input side is electrically coupled to the power supply terminal, the second switching circuit including a second control terminal electrically coupled to the first control terminal of the first switching circuit;
- a third switching circuit electrically coupled in series with the first switching circuit, an output side of the third switching circuit being electrically coupled to the first output terminal;
- a fourth switching circuit electrically coupled in series with the second switching circuit, the fourth switching circuit including a fourth control terminal electrically coupled to the third control terminal of the third switching circuit, and
- a current amplifier configured to:
- detect a difference between an output voltage of the third switching circuit and an output voltage of the fourth switching circuit,
- generate a relative current proportional to the output current, and
- output the relative current to the second output terminal,
- wherein the control circuit is configured to turn on the first switching circuit and the third switching circuit, so that the power supply terminal and the first output terminal become conductive.
10 more elements
Dependencies are inferred from the claim text.