Resistance-based Calibration of a Double Bias Elimination Resistance Measurement Circuit : Calibration for highly accurate measurements over narrow ranges of interest

Measurement bias elimination and ratiometric measurement are techniques in instrumentation which can improve measurement precision. A measurement circuit in which bias was eliminated for the analogue-to-digital conversion of the voltage across the device under test has previously been developed, but it did not eliminate bias for the conversion of the voltage across the ratiometric reference resistor. A modified, double bias elimination circuit has also been previously proposed, which adds elimination of bias for the reference resistor. This circuit would be most useful in specialized investigations of, for example, the behavior of materials over narrow temperature ranges. Here, we describe the circuit’s operation in detail, and propose a cost- effective calibration method to maximize the benefits of the design, based on the high precision and stability of readily- available, low-cost resistors.