Digital flow meter for medical gases

Sensirion: The feeding of special gases such as nitrous oxide, xenon, carbon monoxide etc., is of increasing importance in patient ventilation and anaesthesia. As a consequence, it is increasingly necessary to be able to measure smaller and smaller gas-streams precisely and reliably. With the SFM4100, custom-tailored for integration into anaesthetic equipment, Sensirion AG is responding to this trend in ventilation therapy.

The SFM4100 precision flow meter for air and other non-aggressive gases has an impressively wide dynamic measuring range up to 20 slm. The sensor unit has an I2C interface, provides a fully calibrated and temperature-compensated output signal, and operates reliably at pressures of up to 7 bar.

Its outstanding long-term stability and freedom from drift make the new SFM4100 first choice for products that require a high rate of deployment with long service intervals. Using the ‘Multigas’ feature provided, calibrations for various different gases can be integrated in a single sensor. Self-test features allow testing of the entire signal chain (from capture of the analogue signal through to amplification and A/D conversion, linearization and temperature compensation) while the sensor is in use – a big advantage when used in safety-critical applications.

This extraordinary performance is chiefly due to Sensirion’s tried and tested CMOSens® technology. The sensor unit uses thermal measuring principles to achieve precise, rapid and reliable measurement of gas flow, and the key component is the 3x5mm sensor chip, which houses both the sensor element and the entire analysis electronics.

In addition to mixing gaseous carriers for anaesthesia, the SFM4100 is particularly well suited to integration in other medical and analytical equipment, and for tasks in process automation.

About Sensirion

The Swiss sensor manufacturer Sensirion AG is a leading international supplier of CMOS-based sensor components and systems. Its range of high-quality products includes humidity and temperature sensors, mass flow meters and controllers, gas and liquid flow sensors, and differential pressure sensors. Sensirion supports its international OEM customers with tailormade sensor system solutions for a wide variety of applications. Among others, they include analytical instruments, consumer goods, and applications in the medical technology, automotive and HVAC sectors. Sensirion products are distinguished by their use of patented CMOSens® technology. This enables customers to benefit from intelligent system integration, including calibration and digital interfaces. Sensirion’s competence as a reliable OEM partner is underlined by its quality management system, which was certified in March 2008 in accordance with the ISO/TS 16949 standard.