Posifa Technologies

Posifa Technologies provides high-performance, low-cost gas and liquid flow sensors, air velocity sensors and vacuum sensors that address some of the toughest design challenges in a wide range of industries.

The company’s solid-state micro-electromechanical system (MEMS) flow sensors, which can be packaged in a calibrated module to measure either liquids or gases, can be found in a variety of demanding medical applications, including oxygen concentrators, ventilators, smart inhalers, continuous positive airway pressure (CPAP) equipment and nebulisers.

Posifa can provide factory-calibrated solutions for plug-and-play integration with either analogue voltage or digital I²C outputs. The company can also provide its MEMS flow die, minimally packaged for original equipment manufacturers (OEMs) to integrate into their systems, leveraging their internal resources in module development to maintain that knowledge internally and keep a competitive edge.

High-performance mass air flow sensors for respiratory care

Offered in compact, robust packages, the PMF2000 series of sensors features Posifa’s third-generation thermal flow die, benefitting 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.

The PMF6000 sensor's manifold-mount design removes the need for hoses and external connections.

The PMF83000 sensor features Posifa’s third-generation thermal flow die.

The PMF86000 sensor is designed for respiratory care and other medical and instrumentation applications.

The ‘solid state’ thermal isolation structure eliminates the need for the surface cavity or fragile membrane used in competing technologies, making the sensors resistant to clogging and pressure shock. Ideal for oxygen concentrators, CPAP equipment and nebulisers, PMF2000 sensors measure flow rates from 200 standard cubic centimetres per minute (sccm) to ten standard litres per minute (SLM), offers extremely fast response times of five milliseconds (ms) on average, and is temperature-compensated over the range of 0°C to 50°C.

Mass air flow sensors for bypass assemblies

Optimised for oxygen concentrators, CPAP equipment and nebulisers, the PMF6000 sensor series was developed specifically for users wanting the flexibility of designing their own flow body and restrictor element. The devices’ manifold-mount design removes the need for hoses and external connections, downsizing the system and reducing the number of potential leak points.

By utilising Posifa’s linearised factory calibration, users can create master calibration curves specific to their custom bypass design, with minimal additional corrections in the production process. Unlike off-the-shelf solutions, PMF6000 sensors provide users with a competitive edge by allowing them to perform their own calibration and maintain the values within the company.

Compact mass air flow sensors for medical respiratory care applications

Offered in compact, robust packages, the PMF4000 sensor series features Posifa’s third-generation thermal flow die, benefitting 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 high signal-to-noise performance and repeatability.

The ‘solid state’ thermal isolation structure eliminates the need for the surface cavity or fragile membrane used in competing technologies, making the sensors resistant to clogging and pressure shock. Ideal for oxygen concentrators, CPAP equipment and nebulisers, PMF4000 sensors measure flow rates from 12SLM to 300SLM, offers fast response times of 5ms on average, and is temperature-compensated over the range of 0°C to 50°C. The devices’ linearised output provides maximum flexibility and ease of use.

Condensation-resistant mass air flow sensors

Optimised for oxygen concentrators, CPAP equipment and nebulisers, the PMF83000 series of sensors features Posifa’s third-generation thermal flow die, benefitting 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% full scale (FS).

With its silicon carbide protective film, the sensor die stays robust against water condensation while allowing the highest level of sensitivity and minimising packaging costs. PMF83000 sensors provide both analogue (voltage) and digital I²C outputs in the same package and can be customised with bidirectional flow sensing.

Parylene-coated mass air flow sensors for medical applications

The PMF86000 Series of Gen II mass airflow sensors is designed for respiratory care and other medical and instrumentation applications. The sensors offer increased accuracy, repeatability, and signal-to-noise performance.

The entire sensor printed circuit board (PCB) assembly is coated with parylene, including the sensor die, allowing the sensor to perform reliably in adverse environments and trace amounts of corrosive gases. The PMF86000 series has adopted a single, main flow path design, eliminating the risk of the bypass being clogged by water condensation and dust particles. The sensors provide both analogue (voltage) and digital I²C outputs and support bidirectional flow measurement.

About Posifa Technologies