| 摘要 |
PROBLEM TO BE SOLVED: To shorten an adjustment time for an electric characteristic by laser trimming, by setting a distance to a circuit element to be not smaller than a predetermined value when the laser light is emitted. SOLUTION: Trimming resistors 5a, 5b are arranged to be spaced 70μm from transistors 1a and 4a, 1b and 4b so that a leak current generated by influences of a laser light at the laser trimming time onto the transistors 1a and 1b is not larger than a tolerance, namely, 30nA. In this trim pattern of trimming resistors 5a, 5b, therefore, the transistors 1a and 4a, 1b and 4b are prevented from being influenced by the laser light and malfunctioning. Trimming is carried out while a differential amplifier circuit 2 is continuously driven, and at the same time, an input offset voltage of the differential amplifier circuit 2 is measured. Accordingly, an adjustment work can be done in a short time.
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