We describe a solid-state, silicon integrated, bidirectional flow sensor for respiratory applications. The sensor is a thermal vector sensor. The electronic circuitry for obtaining bidirectional sensitivity is presented together with actual application to a healthy volunteer put on mechanical ventilation. The sensor's input flow range is from -60 to +60 L/min, and its rise-time is ≤40 ms and fall-time is ≤60 ms. The effect of changes in gas composition as used in mechanically ventilated patients on the sensor output signal are estimated to be less than 2%. The temperature sensitivity is about -1.5% per degree Celsius.

, , ,
doi.org/10.1109/10.552250, hdl.handle.net/1765/62978
I E E E Transactions on Biomedical Engineering
Department of Surgery

van Putten, M. J. A. M., van Putten, M. H. P. M., van Putten, A. F. P., Pompe, J., & Bruining, H. (1997). A silicon bidirectional flow sensor for measuring respiratory flow. I E E E Transactions on Biomedical Engineering, 44(2), 205–208. doi:10.1109/10.552250