| 摘要 |
PURPOSE:To decrease the number of components and to improve the reliability, by using a clock source in common for a digital computer and an A/D or A/D converter. CONSTITUTION:The relation of fOSC1<fOSC2 is obtained, where fOSC1 is a clock frequency of a microcomputer 2 and fOSC2 is a clock frequency for a D/A converter 4. A clock 4 is generated from an oscillating circuit comprising a crystal oscillator 5 and an inverter in the converter 4. The oscillating frequency fOSC2 of the clock is 1.5MHz for the upper limit and supplied to a clock terminal of the computer 2 as a pulse 6 of 350kHz at a 4-frequency-division circuit in the converter 4. Then, the common clock is used as the system to operate the computer 2 and the converter 4, thereby reducing remarkably the number of components. |
