AMSYS GmbH & Co. KG, Mainz, April 2021 – When it comes to low pressure measurements and reduced space in always smaller devices combined with high volumes, pressure dies can be the perfect match. Smaller than housed SOIC or DIL pressure sensors, AMSYS also offers the pure silicon-based micromechanical pressure sensing elements (MEMS) for cost sensitive projects. MEMS have long since replaced mechanical sensors with elastic membranes and have proven themselves millions of times over, for example in ventilation technology (HVAC) as well as in medical and automotive technology.
For over 20 years, AMSYS has distributed pressure sensing elements from Silicon Microstructures, Inc. (SMI). The complete range is offered for all pressure types and ranges. A distinction is made between differential/relative and absolute pressure sensing elements. The latter are also available for harsh operating conditions with the SM97A being the successor of the SM98A for 150 and 300 psi (10 and 20 bar).
Very low differential pressures of less than 0.15 psi to 1.5 psi (10 mbar – 100 mbar), on the other hand, can be measured with the SM9520A. An increased sensitivity has been obtained by microstructuring the silicon wafer to form an integrated rigid membrane center for each pressure die. Through additional masking and etching during the manufacturing process, it is possible to structure the membrane in relief on the back and to reinforce its center. This gives the bottom side of the membrane a symmetrical surface thickening. The lateral dimensions, the thickness and the flatness of this thickening are critical variables that have to be controlled and optimized at great expense.
This bending-resistant center results in greater diaphragm deflection at the edges when pressure is applied. Together with adjusted positions of the piezoresistors, the SM9520A has a maximum sensitivity of up to 300 mV/psi with highest linearity (±0.1%).
The range of measuring cells at AMSYS is completed by the differential pressure dies SM30D (successor of the SM30G) and SM30G-Pt for medium pressures between 5 and 30 psi (350 mbar and 2 bar, respectively) and the ultra-compact absolute pressure die SM5108E for 30, 60 and 100 psi (2, 4 and 7 bar).
The Company
AMSYS GmbH & Co. KG is a medium-sized company from Germany that has specialized in innovative solutions in the field of sensor technology since its founding. As a sensor technology distributor, AMSYS is one of the leading specialists in pressure measurement technology in German-speaking countries.
The AMSYS product range includes piezoresistive pressure sensing elements, SMD-mountable transducers, amplified and unamplified as well as calibrated OEM sensors, PCB modules, and ready-to-use pressure transmitters. With sensors and pressure sensing elements covering a pressure range from 25 Pa to 800 bar, AMSYS provides solutions for a wide variety of applications. In addition, the portfolio includes OEM humidity sensors, temperature and inclination sensors, as well as wireless solutions for diverse use cases.
Thanks to the technical expertise of its employees and close collaboration with suppliers, AMSYS also offers customer-specific adaptations of standard products, delivering tailored problem-solving solutions.
Main Characteristics
- 0 – 0.15 psi (10 mbar), 0 – 0.6 psi (40 mbar) and 0 – 1.5 psi (100 mbar) differential pressure
- sensitivity of typ. 45mV (0.15 psi), 90 mV (0.6 psi) and 95 mV (1.5 psi) at 5 Vdd
- linearity of ±0.1% (pressurized from top) and ±0.2% (from bottom)
- footprint only 2,1 x 2,1 mm²
