PRTD Conditioning Circuit and Temperature Controller

The ADT70 provides excitation and signal conditioning for resistance-temperature devices (RTDs). It is ideally suited for 1 kW Platinum RTDs (PRTDs), allowing a very wide range of temperature measurement. It can also easily interface to 100W PRTDs. Using a remote, low cost thin-film PRTD, the ADT70 can measure temperature in the range of -50°C to +500°C. With high performance platinum elements, the temperature change can be extended to 1000°C. Accuracy of the ADT70 and PRTD system over a -200°C to +1000°C temperature range heavily depends on the quality of the PRTD. Typically the ADT70 will introduce an error of only ±1°C over the transducer's temperature range, and the error may be trimmed to zero at a single calibration point.