Design of high precision thermistor temperature measurement system based on AD7799

Aiming at the requirement of fast-response high-precision temperature of ocean expendable probe,this paper presented a design scheme of thermistor temperature measurement based on AD7799.The system took 24-bit Δ-∑ ADC AD7799 as the core,NTC(Negative Temperature Coefficient) thermistor as temperature sensor,and MSP430 microcontroller as MCU,which realized system digitalization.Using multi-points calibration and interpolation method,the system realized high-accurate temperature measurement.The experiments in the laboratory and South China Sea show that the system possesses stable operation and high reliability.The experiment results show that the measurement resolution exceeds 0.001℃ and the measurement accuracy is 0.02℃.