Low-power direct resistive sensor-to-microcontroller interfaces
Rights accessOpen Access
This paper analyzes the energy consumption of direct interface circuits where the data conversion of a resistive sensor is performed by a direct connection to a set of digital ports of a microcontroller (µC). The causes of energy consumption as well as their relation to the measurement specifications in terms of uncertainty are analyzed. This analysis yields a tradeoff between energy consumption and measurement uncertainty, which sets a design procedure focused on achieving the lowest energy consumption for a given uncertainty and a measuring range. Together with this analysis, a novel experimental setup is proposed that allows one to measure the µC’s timer quantization uncertainty. An application example is shown where the design procedure is applied. The experimental results fairly fit the theoretical analysis, yielding only 5 µJ to achieve nine effective number of bits (ENOB) in a measuring range from 1 to 1.38 k. With the same ENOB, the energy is reduced to 1.9 µJ when the measurement limits are changed to 100 and 138 k.
“© © 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”
CitationLopez-Lapeña, O., Serrano, R., Casas, J. Low-power direct resistive sensor-to-microcontroller interfaces. "IEEE transactions on instrumentation and measurement", 1 Gener 2016, vol. 65, núm. 1, p. 222-230.