Current detection circuit, current detection system, and method of adjusting current detection circuit
AssigneesKabushiki Kaisha Toshiba, Toshiba Electronic Devices & Storage Corporation
InventorsKazuhiro Taguchi, Akihiro Murayama
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Abstract
According to one embodiment, a current detection circuit includes a current detection part including an operational amplifier configured to compare a first voltage proportional to a load current with a second voltage proportional to a detection current. The current detection part is configured to output the detection current. The current detection circuit includes an adjustment part configured to generate data in accordance with a result of comparing a monitor voltage proportional to the detection current with a reference voltage, and to adjust an input offset of the operational amplifier.
Claims18
A current detection circuit comprising:
- a current detection part including an operational amplifier configured to receive inputs of a first voltage proportional to a load current and a second voltage proportional to a detection current, and to be adjustable in an input offset voltage by data, the current detection part being configured to output the detection current on a basis of an output of the operational amplifier;
- and
- an adjustment part configured to generate the data in accordance with a result of comparing a monitor voltage proportional to the detection current with a reference voltage, and to adjust an offset of the operational amplifier,
- wherein the adjustment part includes
- a voltage comparison circuit configured to compare the monitor voltage with the reference voltage and output the data,
- a pulse generation circuit configured to generate a predetermined timing signal, and
- a latch circuit configured to latch the data in response to the timing signal.
A current detection system comprising:
- a drive element configured to supply a load current to a load;
- a drive control part configured to supply a drive signal to the drive element to control supply of the load current to the load;
- a current detection part including an operational amplifier configured to receive inputs of a first voltage proportional to the load current and a second voltage proportional to a detection current, and to be adjustable in an input offset voltage by data, the current detection part being configured to output the detection current on a basis of an output of the operational amplifier;
- an adjustment part configured to generate the data in accordance with a result of comparing a monitor voltage proportional to the detection current with a reference voltage, and to adjust an offset of the operational amplifier;
- and
- a control circuit configured to supply an adjustment start signal for starting adjustment of the offset by the adjustment part,
- wherein the adjustment part includes
- a voltage comparison circuit configured to compare the monitor voltage with the reference voltage and output the data,
- a pulse generation circuit configured to generate a predetermined timing signal, and
- a latch circuit configured to latch the data in response to the timing signal.
A method of adjusting a current detection circuit that includes a current detection part including an operational amplifier configured to amplify a difference voltage between a first voltage proportional to a load current and a second voltage proportional to a detection current that is a current reduced at a predetermined ratio with respect to the load current, the method comprising:
- comparing a monitor voltage proportional to the detection current with a reference voltage;
- and
- adjusting an offset of the operational amplifier to cause the monitor voltage to be equal to the reference voltage,
- wherein the adjusting includes
- comparing the monitor voltage with the reference voltage and outputting the data,
- generating a predetermined timing signal, and
- latching the data in response to the timing signal.
Dependencies are inferred from the claim text.