A precision microprocessor-based multislope A/D converter has been designed. It has easily reconfigurable input circuitry that can be used to suit different applications. A low-cost design is presented which attains 16-bit resolution with drift and gain variations as low as 8 p.p.m./ degrees C. The converter is based on the MC6303 microcontroller and is part of a precise five-channel panel thermometer (thermocouple inputs), designed for industrial applications. It is self-contained and equipped with linearizing software and asynchronous communication channel for easy transfer of data to PCs. The analog circuitry of the converter is described in detail, together with the algorithm for correction of errors due to limitations of analog components.
展开▼
