Measurement method and apparatus for simultaneous correction of disturbance and offset of sensor

A measurement apparatus comprising:

• a first sensor of a Wheatstone bridge type;
• a second sensor of a Wheatstone bridge type connected with the first sensor as a differential structure;
• a current generator configured to apply a bias current to the first sensor and the second sensor;
• a first measurement unit configured to measure a voltage of the first sensor;
• a second measurement unit configured to measure a voltage of the second sensor;
• and
• a calculator configured to calculate a final measurement value based on voltages measured by the first measurement unit and the second measurement unit when a bias current is applied, in a first direction, to the first sensor and the second sensor, and voltages measured by the first measurement unit and the second measurement unit when a bias current is applied to the first sensor and the second sensor in a second direction opposite to the first direction,
• wherein the final measurement value is (V1−V2−V3+V4)/4,
• where V1 is a voltage of the first sensor which is measured by the first measurement unit when a bias current is applied to the first sensor and the second sensor, V2 is a voltage of the second sensor which is measured by the second measurement unit when a bias current is applied to the first sensor and the second sensor, V3 is a voltage of the first sensor which is measured by the first measurement unit when a bias current of an opposite direction is applied to the first sensor and the second sensor, and V4 is a voltage of the second sensor which is measured by the second measurement unit when a bias current of the opposite direction is applied to the first sensor and the second sensor.

A measurement method using a measurement apparatus comprising a first sensor and a second sensor of a Wheatstone bridge type connected with each other as a differential structure, the measurement method comprising:

• first measuring a voltage of the first sensor and a voltage of the second sensor in a state in which a current to be measured through the first sensor and the second sensor flows through a current path in a first direction;
• second measuring a voltage of the first sensor and a voltage of the second sensor in a state in which a current flows through the current path in a second direction opposite to the first direction;
• and
• calculating a final measurement value based on the voltages measured in the first measuring and voltages measured in the second measuring,
• wherein the final measurement value is (V1−V2−V3+V4)/4,
• where V1 is a voltage of the first sensor measured in the first measuring, V2 is a voltage of the second sensor measured in the first measuring, V3 is a voltage of the first sensor measured in the second measuring, and V4 is a voltage of the second sensor measured in the second measuring.

A The measurement apparatus comprising:

• a first sensor of a Wheatstone bridge type;
• a second sensor of a Wheatstone bridge type connected with the first sensor as a differential structure;
• a first measurement unit configured to measure a voltage of the first sensor;
• a second measurement unit configured to measure a voltage of the second sensor;
• and
• a calculator configured to calculate a final measurement value based on voltages measured by the first measurement unit and the second measurement unit in a state in which a current to be measured through the first sensor and the second sensor flows through a current path in a first direction, and voltages measured by the first measurement unit and the second measurement unit in a state in which a current flows through the current path in a second direction opposite to the first direction,
• wherein the final measurement value is (V1−V2−V3+V4)/4,
• where V1 is a voltage of the first sensor which is measured by the first measurement unit in a state in which a current to be measured through the first sensor and the second sensor flows in the current path, V2 is a voltage of the second sensor which is measured by the second measurement unit in a state in which a current to be measured through the first sensor and the second sensor flows through the current path, V3 is a voltage of the first sensor which is measured by the first measurement unit in a state in which a current flows through the current path in an opposite direction, and V4 is a voltage of the second sensor which is measured by the second measurement unit in a state in which a current flows through the current path in the opposite direction.

A non-transitory computer-readable recording medium which has a program stored thereon, for performing a measurement method comprising:

• first applying a bias current, in a first direction, to a first sensor and a second sensor of a Wheatstone bridge type connected with each other as a differential structure;
• first measuring a voltage of the first sensor and a voltage of the second sensor;
• second applying a bias current to the first sensor and the second sensor in a second direction opposite to the first direction;
• second measuring a voltage of the first sensor and a voltage of the second sensor;
• and
• calculating a final measurement value based on the voltages measured in the first measuring and the voltages measured in the second measuring,
• wherein the final measurement value is (V1−V2−V3+V4)/4,
• where V1 is a voltage of the first sensor measured in the first measuring, V2 is a voltage of the second sensor measured in the first measuring, V3 is a voltage of the first sensor measured in the second measuring, and V4 is a voltage of the second sensor measured in the second measuring.