A Design of High-Precision Digital Resistance Meter

This paper introduces a system design of high-precision resistance meter based on a high-performance microprocessor MC9S08AC16 and a high-resolution A / D converter AD7705. The system block diagram, hardware circuits, software and test results are given. Functions such as automatic range switching, zero adjustment, software error compensation and auto distinguish based on error level are added to the meter. Experiments show that the meter has many advantages such as easy design, high accuracy, compact structure, high reliability and low cost.