LBA Low Pressure Sensors Offer Special Versions With Highest Resolution for Respiration Applications

Sensortechnics’ LBA series offers differential low pressure sensors based on thermal mass flow measurement of air through a micro-flow channel integrated within the silicon sensor chip. The sensors are ideal for differential pressure flow measurement where the pressure drop across a flow element is a measure of the volumetric flow rate. For high performance medical respiratory devices it is essential to detect very small flows around the zero flow point while additionally being able to measure full scale flows of several hundreds of l/min. For these demanding requirements Sensortechnics now offers special versions of its LBA sensors with increased resolution of 0.01 % in the lower pressure range and at the same time high dynamic ranges greater than 10,000.

The LBA sensors feature an innovative MEMS construction which integrates the micro-flow channel and fully analog CMOS signal conditioning within the silicon sensor chip. This decreases the flow through the LBA sensor by several magnitudes compared to other flow-based pressure sensors and allows high immunity to condensation and dust contamination. Further, the LBA differential pressure sensors can be used with long connecting tubes and input filters without the need to recalibrate or correct the output signal. Because the flow impedance is predefined at the sensor chip level the LBA series provides very small and cost-effective PCB-mountable housings.

Important features of the new LBA sensors:

• 0.01 % resolution and high dynamic ranges greater than 10,000
• High immunity to dust contamination and condensation
• Long connecting tubes or input filters do not affect sensor performance
• Very small PCB-mountable housings

Sensortechnics’ new LBA differential pressure sensors with 0.01 % resolution are ideal for many medical respiratory devices such as e.g. ventilators, spirometers, sleep diagnostic equipment and CPAP machines.