| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic sensor whose linearity of an output with reference to a detection magnetic field is superior, whose temperature characteristic is superior, which is of high sensitivity and which is compact. SOLUTION: A high-frequency current is energized to two MI elements 4 to which DC magnetic fields of mutually opposite polarities are applied by an oscillation circuit 5. Their outputs are converted into DC signals by a detection circuit 6 so as to be differentially amplified by an amplifier circuit 7, and its output is fed back to negative-feedback coils 2. The high-frequency energization current which is applied to the MI elements 4 can be supplied stably, a change in the magnetic fields of the MI elements 4 can be detected with good efficiency, and a circuit constitution becomes simple. When a set current is made to flow to a diode, the detection circuit 6 can convert, with high sensitivity, the outputs of the MI elements 4 into the DC signals even when an input amplitude is small. In addition, when the outputs of the MI elements 4 are added and composed, the temperature characteristic of the diode and its change with the passage of time can be excluded, and a superior magnetic sensor module can be provided.
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