| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a current sensor that dynamically adjusts an offset amount without discontinuing measurement of a current value and has high responsiveness. <P>SOLUTION: The current sensor 1 includes a shunt resistance sensor 20 and a Hall element sensor 10. This current sensor 1 includes a differential amplifier 31, a sample and hold circuit 32, a digital storage circuit 40, a switch 33, a substracter 34 and a control part 35 controlling these elements. The control part 35 selects an output signal of the sample and hold circuit 32 as an offset amount by the switch 33 when a sensor signal output from the shunt resistance sensor 20 comes to have a prescribed value or less, while it starts driving of the digital storage circuit 40. When storing of the digital storage circuit 40 is completed thereafter, an output signal of the digital storage circuit 40 is selected as the offset amount by the switch 33. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
