PMF5000 Series Mass Air Flow Sensor For Medical Devices

Posifa designed the PMF5000 series of mass air flow sensors specifically for portable medical devices. The sensor is fast and accurate, enabling the precise amount of gas to be delivered in a pulse mode. The sensor’s small footprint fits nicely inside a spaceconstrained housing. The push-to-connect fittings supports efficient assembly. The flow direction (forward or backward) can be customized to work with an existing system layout.

PMF5000 features 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, and repeatability. The “solid state” thermal isolation structure on the sensor die eliminates the need for surface cavity or fragile membrane used in competing technologies, making the sensor resistant to clogging and pressure shock.

The PMF5000 series includes the analog output PMF5000V and the digital I²C output PMF5000D.

The PMF5000 series is a proven product that has been used in quantity in FAA approved, FDA cleared, and CE certified medical devices.

Absolute Maximum Ratings

• Operating temperature: −25 °C to 85 °C
• Calibrated temperature range: 0 °C to 50 °C
• Storage temperature: −40 °C to 90 °C
• Humidity: 0% to 100% RH, non‑condensing
• Shock: 100g peak (5 drops, 3 axis)
• Operating pressure: 25 psi
• Supply: 5 V (typ.), ~20 mA