SMI introduces ultra-low gauge pressure sensor with industry accuracy

Calibrated and compensated pressure ranges as low as 250 Pa. SMI (Silicon Microstructures, releases the SM923X Series of ultra-low pressure sensor systems. With the SM923X Series SMI extends the limit of ultra-low gauge pressure sensing to as low as 250 Pa (1 inH2O). The fully temperature compensated and pressure calibrated sensor enables precise pressure sensing in industrial, HVAC and medical applications. Industry output accuracy (1% FS) and long-term stability is achieved by combining SMI’s proprietary MEMS pressure transducer with a state-of-the-art signal-conditioning IC in one package.

The SM923X Series was developed to meet the challenging reliability requirements of the industrial, HVAC and medical applications. SMI’s compact solution replaces traditional bulky and costly equipment and the SM923X series improves system efficiency with accurate and reliability performance. The total accuracy error after board mount and system level autozero is less than 1% full scale over the entire compensated temperature range. The 16 bit resolution provides the ability to resolve signals as small as 0.0038 Pa. The excellent warm-up behavior and long-term stability further assures its expected performance over the life of the part.

Easy system integration

The SM923X sensors are fully calibrated and ready to use. The digital I2C Interface allows easy system integration. A deep sleep mode enables new customer applications including wireless sensing for HVAC. The SMI solution integrates high order noise filtering and provides low noise and extremely low EMI susceptibility. The small SO16 package with dual vertical port allows for easy system integration and pressure connection, while the MEMS sensor itself is robust with high burst pressure. Implementation is further eased by the sensor’s immunity to mounting orientation and vibrations.

The gauge pressure sensor system is available in three configurations: SM9233 (0 to +250 Pa / 0 to 1 inH2O), SM9235 (0 to +300 Pa / 0 to 1.2 inH2O) and SM9236 (0 to +600 Pa / 0 to 2.4 inH2O). The devices are available for customer sampling and are released for volume production.

Key applications: Pressure switches, VAV and respiratory devices

The SM923X Series empowers accurate pressure sensing in industrial control systems like pressure switches and pneumatic valves by e.g. detecting a leakage. Another application is to measure gas pressure in vacuum pumps. In HVAC equipment pressure sensors are used for filter monitoring as well as for VAV control. With the help of SMI’s solution air can be distributed in smarter ways and thus enable energy savings.

In medical applications ultra-low gauge pressure sensors are utilized to determine ventilation pressure and suction pressure in e.g. respiration devices. The integration and use in breathing equipment is eased by the insensitivity of the sensor to the mounting orientation, its high resolution and low noise performance.

The SM923X Series complements SMI’s ultra-low pressure sensor portfolio with a solution for gauge pressure. Please visit the product page for more information on the SM923X and the rest of the SM9000 Family, including the differential ultra-low pressure sensor SM933X.

“Decades of experience in low pressure sensing are reflected in the SM9000 Family. The SM923X Series completes SMI’s solutions offering on the low pressure side and puts us at the forefront of the market with the lowest available pressure range, with the respectively highest accuracy,” says Mike Klitzke, VP of R&D and Business Development of SMI. “We are excited to see how customers can increase efficiency on the system level by utilizing our sensors.”