A low-cost, high-accuracy temperature sensor array

Real-time two-dimensional mapping of temperature for totally or partially concealed medium- or large-sized surfaces is necessary in a variety of applications. In these cases, an array of thermistors can provide a good solution. This article describes a low-cost, scalable array of thermistors (maximum size 8 × 8), together with high-precision reading electronics. To select the electronics, which produced the best results in the array reading, two proposals from the literature were implemented and the performances were assessed taking into consideration different array sizes and thermistor resistance values. The precision of the readings was evaluated using the best electronic solution, with a maximum error of 0.036 °C, taking into account only the error in the resistance measurement and the manufacturer data. The sampling period of the complete array was 58.5 ms, thus allowing the sensor to be used in real-time applications.