| 摘要 |
<p>PROBLEM TO BE SOLVED: To ease limits of an integrator output range imposed by offset components of a Hall element and preamplifier.SOLUTION: A magnetic detection device comprises: a chopper-driven Hall element 1; a preamplifier 3 for amplifying output of the Hall element 1; a first chopper switch 2 connected between the Hall element 1 and the preamplifier 3; an integral AD converter 4, which includes an integrator and a second chopper switch located on an input side of the integrator, for AD-converting output of the preamplifier 3 to obtain a magnetic signal; a chopper clock signal generator circuit 6; and a correction DA converter 5 which generates a correction signal for correcting the output of the preamplifier 3 using an output signal of the integral AD converter 4 in each offset measurement sequence. In each magnetic signal measurement sequence for measuring the magnetic signal, the integral AD converter 4 AD-converts the output of the preamplifier 3 while making correction using the correction signal from the correction DA converter 5.</p> |
