| 摘要 |
PURPOSE:To detect the slight change of a magnetic field in a high magnetic field highly accurately and to obtain a differential output easily without separating MR elements in the array direction of magnetic patterns by making current corresponding to the detecting output of the external magnetic field by the MR elements flow into a conductive film and applying a magnetic field to the MR element in the reverse direction against the external magnetic field. CONSTITUTION:A differential output obtained from a connection point 19 is fed back to a conductive film 16 and a load resistor 22 connected to the conductive film 16 in a series through an amplifier 21 and a reverse magnetic field -H'S against an external magnetic field HS is applied to the MR elements 13a, 13b by the current flowing into the conductive film 16. The change of current flowing into the conductive film 16 is taken out from an output terminal 28 as voltage change by a load resistor 22. Said constitution applies the magnetic field Hs/hFE (hFE is a value corresponding to the reverse magnetic field -H'S) to the MR elements 13a, 13b against the external magnetic field HS, so that the magnetic field hFE times that of no feedback can be detected. |
