An Implementation of a Linear-sensitivity Pressure-sensor System

Abstract

In this work, we designed and developed an integrated pressure-sensor system with a perfectly linear sensitivity. We used a resistive-type indicator pressure-sensor in order to measure a gas-level which is observed to be inversely proportional to sensor output-resistance. Then, the output resistance was converted into the corresponding voltage which was processed via several sensor-conditioning steps (buffering, level-shifting, amplification). We analyzed the sensitivity errors at level-shifting stage and then proposed the new and simple approach for a perfectly linear-sensitivity in sensor-conditioning processes by using only a constant voltage supply without the potentiometer, which is common in previous works. Even though the sensor output was generally adjusted to the full scale of the reading, we have a perfectly linear sensitivity and the devices fabricated exhibited linear characteristics without any sensitivity error.