This paper introduces a kind of intelligent dc potentiometer unit of the design of the software and hardware. P89C58 of PHILIPS is a large capacity single-chip (32K Flash);it met the five kinds of thermocouple EMF / temperature form of storage needs; the application of 24 bits Σ—△A/D converter AD7714 make the measurement unit to have high resolution and precision; the check form method in the software can directly read the value of the temperature corresponding potential of 5 thermocouples. It eliminates the system errors of the meter that adjusting the zero and the full scale with the software method; The use of a digital liquid crystal 8, and to facilitate the potential difference of readings; the target of the adjustable mV signal source can satisfy the needs of verifying some industry meters; the whole instrument designs low-power, improved the form of equipment supply, use city electricity supply and the general power of dual-use dry-cell batteries, eliminating the supply of different places due to equipment caused by the inconvenient factors. DC potentiometer traditional use of these steps is not only more, but also vulnerable to instability in the work of power, sensitivity galvanometer, standard cell and the environment impact of temperature and other relevant factors. Therefore, the use of modern electronic technology to develop a mV signal calibrator is of great significance.
Keywords DC potentiometer;mV Signal Generator;AD conversion;Low Consume