An earlier Design Idea described how to linearize the output of an RTD (resistance-temperature-detector) sensor and how to calculate the resistor values using a spreadsheet (Reference 1). That idea ...

The old saying “if it ain’t broke, don’t fix it” cautions against tampering with something that performs reliably and regularly proves its worth. Arguably, this advice applies to the circuit design ...

RTD sensors are available using two-, three-, and four-wire configurations, which differ in their use of sense wires (Fig. 1a, 1b, and 1c, respectively).

It also cuts the number of RTD array connections (feedthroughs) from 4N to 4 + N. For 28 sensors, the resulting savings are 2N − 2 − N = 26 inputs and 4N − 4 − N = 80 feedthroughs.

This work presents the design, implementation, and experimental evaluation of a novel measurement circuit for four-wire resistive sensors, such as RTD thermal sensors. The proposed circuit ...