摘要 |
PROBLEM TO BE SOLVED: To provide a detecting circuit capable of detecting precisely a rare short circuit condition generated in a load. SOLUTION: In order to drive an L load 2, FETs 1b, 3b are arranged to be mirror-paired with FETs 1a, 3a arranged in a power source side and a ground side respectively, and currents in response to mirrored currents of the first and second currents flowing in FETs 1b, 3b are made to flow in current mirror circuits 22, 23, and a mirror ratio is set in the former to make a current ratio of the first current side large, and a mirror ratio is set in the latter to make a current ratio of the second current side large. When the first current gets larger than the second current, a current flowing in a transistor 22a is increased via a mirror circuit 37 to set a transistor 28 to get conductive, and a current flowing in a transistor 23b is increased via a mirror circuit 40 to set a transistor 34 to get conductive, when the second current gets larger than the first current. COPYRIGHT: (C)2006,JPO&NCIPI
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