ZERO POINT ADJUSTING CIRCUIT AND ZERO POINT ADJUSTING METHOD

PROBLEM TO BE SOLVED: To further appropriately adjust a zero point in a zero point adjusting device and a zero point adjusting method of a measuring instrument. SOLUTION: This zero point adjusting device 1 of the measuring instrument includes a bridge circuit 10, and resistance elements RC0-RC3 whose one-side terminals are connected to an output terminal b of the bridge circuit. A CPU (Central Processing Unit) 40 has a switching means 41 for selecting one from three connection states of the other terminal of each of the resistance elements RC0-RC3 and performing switching, and controls the switching means 41 based on an output signal of an ADC (Analog to Digital Converter) circuit 22. Specifically, management data described by 4 digits of ternary is used. Each of the 4 digits corresponds to each of the resistance elements RC0-RC3, and, as each digit value, one is specified from three connection states of the resistance elements RC0-RC3. The CPU 40 determines whether the level of the output signal exists in tolerance, sequentially selects a digit to be processed in the management data based on the determination result, and sequentially varies the value of the selected digit. COPYRIGHT: (C)2009,JPO&INPIT