Signal processing circuit
AssigneesKabushiki Kaisha Toshiba, Toshiba Electronic Devices & Storage Corporation
InventorHideaki Majima
Life of this patent
Estimating the term…
Abstract
According to one embodiment, a signal processing circuit includes a first voltage setting circuit that sets a reference voltage on an input side of an isolator, a variable gain amplifier circuit that amplifies an output signal of the isolator, a DC offset adjustment circuit that adjusts an offset of the variable gain amplifier circuit, a second voltage setting circuit that sets a reference voltage on an output side of the isolator, and a control circuit that controls the DC offset adjustment circuit in response to a result of comparison of an output voltage of the variable gain amplifier circuit with an output voltage of the second voltage setting circuit.
Claims20
A signal processing circuit, comprising:
- an isolator with an input side and an output side that are electrically insulated;
- a first voltage setting circuit that is provided on the input side of the isolator and outputs a reference voltage on the input side of the isolator to the input side of the isolator;
- a variable gain amplifier circuit that amplifies an output signal of the isolator;
- a DC offset adjustment circuit that adjusts an offset of the variable gain amplifier circuit;
- a second voltage setting circuit that sets a reference voltage on the output side of the isolator;
- a comparison circuit that compares an output voltage of the variable gain amplifier circuit with an output voltage of the second voltage setting circuit;
- and
- a control circuit that controls the DC offset adjustment circuit in response to an output signal of the comparison circuit.
A signal processing circuit, comprising:
- an isolator with an input side and an output side that are electrically insulated;
- a first voltage setting circuit that is provided on the input side of the isolator and outputs a reference voltage on the input side of the isolator to the input side of the isolator;
- a variable gain amplifier circuit that amplifies an output signal of the isolator;
- a DC offset adjustment circuit that adjusts an offset of the variable gain amplifier circuit;
- a second voltage setting circuit that sets a reference voltage on the output side of the isolator;
- a comparison circuit that compares an output voltage of the variable gain amplifier circuit with an output voltage of the second voltage setting circuit;
- and
- a control circuit that controls the DC offset adjustment circuit in response to an output signal of the comparison circuit, wherein
- the first voltage setting circuit includes:
- a first transistor with a main current path that is connected to a constant current source in series;
- a voltage/current conversion circuit that converts a voltage that is generated on the main current path of the first transistor into a current;
- and
- a differential amplifier circuit with an input terminal that is supplied with an output current from the voltage/current conversion circuit.
Dependencies are inferred from the claim text.