| 摘要 |
<p>PURPOSE:To increase the precision of trimming by a method wherein a third resistor is provided in parallel with a first resistor to realize the relative precision of the first resistor and a second resistor which are the factors of a balance characteristic, first the absolute precision of the first resistor is trimmed, and then the third resistor is trimmed. CONSTITUTION:A third resistor R3 is provided in parallel with a first resistor R1 so that the relative precision of a second resistor R2 between terminals 1 and 2 and of the first resistor R1 between terminals 3 and 4 be set within + or -0.1%. So as to obtain a relative precision + or -0.1% in relation to an absolute precision 100OMEGA+ or -0.5%, for instance, the first resistor R1 is set beforehand to be of about 102OMEGA, somewhat larger than 100OMEGA of the second resistor R2. First the second resistor R2 is trimmed to be of 100OMEGA+ or -0.5%, and then the third resistor R3 is trimmed so that a specific precision be within + or -0.1%. When the precision is set thereby within the relative precision + or -0.1%, trimming is ended. Since the working rate of the third resistor R3 contributing to + or -0.1% is 1/20 of 100OMEGA, the trimming can be performed very easily.</p> |
