Abstract: A multicopter includes a body, propellers, each of which is rotated by a motor to generate lift for the body, a main controller configured to supply a speed instruction signal to the motor, a supply circuit configured to supply a torque current signal and a field current signal obtained from the motor, and a motor drive control device.

Abstract: A full bridge circuit comprises first to fourth magnetic resistance elements. The first and fourth magnetic resistance elements have a first polarity, while the second and third magnetic resistance elements have a second polarity. A comparison circuit compares a first value indicating a difference between a potential of a first connecting node and a first potential and a second value indicating a difference between a potential of a second connecting node and a second potential to determine presence/absence of an external magnetic field. An initial magnetization vector of a magnetization free layer of the first magnetic resistance element is the reverse of that of a magnetization free layer of the second magnetic resistance element. An initial magnetization vector of a magnetization free layer of the third magnetic resistance element is the reverse of that of a magnetization free layer of the fourth magnetic resistance element.

Abstract: A current sensor comprises: a plurality of magnetoresistance elements whose resistance value changes by application of an current-induced magnetic field from a current-to-be-measured; and a selection circuit that selects one magnetoresistance element from these plurality of magnetoresistance elements and outputs a signal of a selected magnetoresistance element. In the plurality of magnetoresistance elements, relationships between a magnitude of the applied current-induced magnetic field and the resistance value are different from each other.

Abstract: A multicopter includes a body, propellers, each of which is rotated by a motor to generate lift for the body, a main controller configured to supply a speed instruction signal to the motor, a supply circuit configured to supply a torque current signal and a field current signal obtained from the motor, and a motor drive control device.

Abstract: A current sensor comprises a plurality of magneotresistance elements and a first magnetic body. The plurality of magneotresistance elements each have their resistance value change by being applied with an current-induced magnetic field from a current to be measured. The first magnetic body applies a first offset magnetic field substantially parallel to the current-induced magnetic field applied to a first magneotresistance element of the plurality of magneotresistance elements. Moreover, a smart meter according to an embodiment of the present invention has, for example, the current sensor according to the present embodiment installed therein.

Abstract: A full bridge circuit comprises first to fourth magnetic resistance elements. The first and fourth magnetic resistance elements have a first polarity, while the second and third magnetic resistance elements have a second polarity. A comparison circuit compares a first value indicating a difference between a potential of a first connecting node and a first potential and a second value indicating a difference between a potential of a second connecting node and a second potential to determine presence/absence of an external magnetic field. An initial magnetization vector of a magnetization free layer of the first magnetic resistance element is the reverse of that of a magnetization free layer of the second magnetic resistance element. An initial magnetization vector of a magnetization free layer of the third magnetic resistance element is the reverse of that of a magnetization free layer of the fourth magnetic resistance element.

Abstract: A current sensor comprises a plurality of magnetoresistance elements and a first magnetic body. The plurality of magnetoresistance elements each have their resistance value change by being applied with an current-induced magnetic field from a current to be measured. The first magnetic body applies a first offset magnetic field substantially parallel to the current-induced magnetic field applied to a first magnetoresistance element of the plurality of magnetoresistance elements. Moreover, a smart meter according to an embodiment of the present invention has, for example, the current sensor according to the present embodiment installed therein.

Abstract: A current sensor comprises: a plurality of magnetoresistance elements whose resistance value changes by application of an current-induced magnetic field from a current-to-be-measured; and a selection circuit that selects one magnetoresistance element from these plurality of magnetoresistance elements and outputs a signal of a selected magnetoresistance element. In the plurality of magnetoresistance elements, relationships between a magnitude of the applied current-induced magnetic field and the resistance value are different from each other.