Detection circuit

A detection circuit of which wiring is made at a multilayer board having at least two layers, the detection circuit comprising:

• a detector interposed on a path of current or voltage in an electric circuit;
• a differential amplifier which outputs voltage according to the current or the voltage detected by the detector;
• a plus-side detection wire connected between a plus input terminal of the differential amplifier and one end of both ends at which the detector is connected to the path;
• a minus-side detection wire connected between a minus input terminal of the differential amplifier and another end of both ends;
• at least one first detection wire connected in parallel to at least a part of the plus-side detection wire between the one end of the detector and the plus input terminal of the differential amplifier;
• and
• at least one second detection wire connected in parallel to at least a part of the minus-side detection wire between the other end of the detector and the minus input terminal of the differential amplifier, wherein
• at the same layer of the multilayer board, each detection wire included in the plus-side detection wire and the first detection wire is arranged so as to be adjacent to, in a direction parallel to a surface of the multilayer board, any of detection wires included in the minus-side detection wire and the second detection wire, and
• at different layers of the multilayer board, each detection wire included in the plus-side detection wire and the first detection wire is arranged so as to be opposed to, in a direction perpendicular to the surface of the multilayer board, any of detection wires included in the second detection wire and the minus-side detection wire.

A detection circuit of which wiring is made at a multilayer board having at least two layers, the detection circuit comprising:

• a detector interposed on a path of current or voltage in an electric circuit;
• a differential amplifier which outputs voltage according to the current or the voltage detected by the detector;
• a plus-side detection wire connected between a plus input terminal of the differential amplifier and one end of both ends at which the detector is connected to the path;
• a minus-side detection wire connected between a minus input terminal of the differential amplifier and another end of both ends;
• at least one first detection wire connected in parallel to at least a part of the plus-side detection wire between the one end of the detector and the plus input terminal of the differential amplifier;
• at least one second detection wire connected in parallel to at least a part of the minus-side detection wire between the other end of the detector and the minus input terminal of the differential amplifier;
• and
• through-holes or via-holes provided at both ends of each of the plus-side detection wire and the minus-side detection wire arranged at a first layer of the multilayer board, wherein
• the first detection wire and the second detection wire are arranged at a second layer of the multilayer board electrically connected with the first layer via the through-holes or the via-holes,
• both ends of the plus-side detection wire are respectively connected to both ends of the first detection wire via the through-holes or the via-holes,
• both ends of the minus-side detection wire are respectively connected to both ends of the second detection wire via the through-holes or the via-holes, and
• a pair of wires composed of the first detection wire and the second detection wire have equal lengths and are arranged so as to be point-symmetric with respect to a center of gravity among connection parts where the first detection wire and the second detection wire, and the through-holes or the via-holes, are connected to each other.

A detection circuit of which wiring is made at a board, the detection circuit comprising:

• a detector interposed on a path of current or voltage in an electric circuit;
• a differential amplifier which outputs voltage according to the current or the voltage detected by the detector;
• a plus-side detection wire connected between a plus input terminal of the differential amplifier and one end of both ends at which the detector is connected to the path;
• a minus-side detection wire connected between a minus input terminal of the differential amplifier and another end of both ends;
• at least one first detection wire connected in parallel to at least a part of the plus-side detection wire between the one end of the detector and the plus input terminal of the differential amplifier;
• and
• at least one second detection wire connected in parallel to at least a part of the minus-side detection wire between the other end of the detector and the minus input terminal of the differential amplifier, wherein
• at the same surface of the board, a plurality of pairs composed of each detection wire included in the plus-side detection wire and the first detection wire and each detection wire included in the minus-side detection wire and the second detection wire are arranged in parallel, and two, of the detection wires, that are adjacent to each other and are included in two adjacent pairs among the plurality of pairs, are connected to the plus input terminal or the minus input terminal of the differential amplifier.