| 摘要 |
PURPOSE:To use an electronic balance for various electronic balances different in weighing without degrading the conversion precision of an A/D converter neither changing an amplifying circuit arranged in the preceding stage, by controlling the integral time of an analog signal with a soft timer set in a microcomputer. CONSTITUTION:Each of CPUs 5a-5c is provided with a soft timer which outputs a switching command Sa at a prescribed timing, and the set time of the soft timer in the CPU5a is fixed, and that in the CPU5b and the CPU5c is variable. Programs constituting soft timers or set times of soft timers are changed to obtain a digital signal of a desired count number. Consequently, the change of degree of amplification of amplifying circuit B arranged in preceding stages of A/D converters C1, C2, and C3 is made unnecessary, and this electronic balance can be used for various electronic balances different in weighing as it is. |
