POTENTIAL FOR A SMART SENSOR-BASED ON AN INTEGRATED SILICON ANEMOMETER

An intelligent silicon anemometer is being developed with a bridge which employs diffused resistors operated at an elevated temperature to achieve a high dynamic range. A novel technique achieves thermal feedback in a double Wheatstone bridge configuration using integrated temperature-insensitive operational amplifiers. The aim is to achieve high sensitivity, immunity from humidity and from ambient temperature variations. Early devices have been fabricated in CMOS technology demonstrating the efficient implementation of high performance analogue electronics suitable for using low-cost standard IC fabrication processes. An application for this integrated smart silicon anemometer is to replace the more cumbersome mechanical peak-flow meters used in the treatment of sufferers of chronic obstructory pulmonary diseases [1]. The reliability and immunity from interference can be further improved by integrating the complete sensor system on a single monolithic CMOS or BiCMOS chip.