Mass air flow sensors enhanced with parylene coating

Designed to provide an extra level of protection for reliable performance in harsh environments with high humidity and trace amounts of corrosive gases, new PMF83000 and PMF86000 series sensors have been enhanced with a parylene coating over the entire PCB assembly — including the sensor die.

Featuring robust packages, the sensors introduced today serve as key components in ventilators, respirators, oxygen concentrators, nebulizers, and CPAP equipment, where they control the volume of air flow to patients.

In addition, the devices provide mass flow measurement in anesthesia delivery, fuel cell control, and environmental monitoring equipment.

The PMF83000 and PMF86000 series feature Posifa's third-generation thermal flow die, benefiting from the latest innovations in microfabrication.

The sensor die uses a pair of thermopiles to detect changes in temperature gradient caused by mass flow, delivering excellent signal-to-noise performance and repeatability of 0.5 % F.S.

Both series feature a single main flow path design, eliminating the risk of the bypass being clogged by water condensation and dust particles.

Measuring flow rates from 15 SLM to 100 SLM and 50 SLM to 300 SLM, respectively, the PMF83000 and PMF86000 series offer extremely fast response times of 5 ms typical and operate over temperature ranges of -25 °C to +65 °C.

The devices provide both analogue (voltage) and digital I²C outputs in the same package and support bidirectional flow measurement. Buyers can contact Posifa to discuss options for customising the sensors' features and specifications.

Samples and production quantities are available.