| 摘要 |
PROBLEM TO BE SOLVED: To suppress the influence of an input offset voltage of a magnetic field sensor, and manufacture the magnetic field sensor capable of highly accurate detection regardless of dispersion in the manufacture. SOLUTION: At first timing, a voltage between terminals B, B' of a Hall element 1 is inputted into a voltage amplifier 30, and a switch 5 is closed, and a capacitor 4 is charged. At second timing, a voltage between terminals A, A' of the Hall element 1 is inputted into the voltage amplifier 30 so as to have the polarity reverse to that of the first timing, and the switch 5 is opened, and a detection voltage wherein an input offset voltage is compensated is outputted from output terminals 6, 7. The Hall element 1 and a resistor 22 are formed by the same material and in the same manufacturing process (for example, by diffusing an n-type impurity on a p-type semiconductor substrate), and a resistor 23 is formed by a poly-silicon resistance having small dispersion of the characteristic.
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