Low pressure sensors for filter control - SM9233

The SM9233 pressure sensor is offered in a JEDEC compliant SOIC-16 package for surface mount device (SMD) on printed circuit boards and has two vertical tube connectors. It can be placed in the PCB design like an IC and mounted on PCBs using a reflow process to save space. In addition to the silicon sensing element, the ASIC for data processing is also built directly into the package.

During manufacturing, the low pressure sensors are individually linearized, calibrated and temperature compensated. The corresponding data is stored in the integrated ASIC. Thus, no additional circuitry, such as a compensation network, is required. Two signals in I²C format are available as output signal, which are output proportional to the differential pressure and the temperature. To check the proper functioning of the sensor, the sensor voltage, the measuring bridge and the data transmission can be controlled via the I²C bus.

With an ADC resolution of 16 bit and an accuracy* of typ ±0.5 % FS in the entire calibration temperature range (-20 to +85 °C), the sensor is particularly suitable for industrial applications such as filter control in air conditioning, domestic or clean room technology, but also has medical applications (e.g. respiration control, flow measurement, etc.). Other models in the series have pressure ranges of 0 - 300 Pa and 0 - 600 Pa.

AMSYS also offers the pressure sensors in a bidirectional differential version with ±125 Pa or ±250 Pa. The special feature of these differential sensors is the fact that they can measure both negative and positive pressure, which is crucial in respiratory control, for example (reversal of direction during inhalation and exhalation).

* Accuracy is defined by AMSYS as the total error, which includes calibration errors, temperature errors and all stochastic errors (hysteresis, non-linearity and reproducibility).