For all Freescale standard pressure sensor products, any environment other then dry air, will have some impact on the reliability and lifetime of the product. Freescale's silicon pressure sensors are NOT compatible with oil, gas, petrol and water or water vapors, or chemicals. A determination must be made if this impact is acceptable for the application.
In general, Freescale pressure sensors were designed, and are warranted, for use in clean dry air only as mentioned. Our media compatibility disclaimer suggests that our customers are responsible for determining media compatibility in other environments. Customers are urged to conduct their own in-house evaluations and characterizations to determine if our devices are suitable for use in their non-clean dry air environment.
The MPL3115A2 was tested at 85°C with at 85%RH for a prolonged period of time with bias. The parts were then re-tested within 48 hours to make sure they met the spec.
Usually in a water measurement application, a head tube is used. This is simply a piece of tubing between the sensor and the container in which the water level or pressure needs to be measured. Air is trapped in the tube and this isolates the sensor from the liquid water.
I would like refer to the following application note that would be worth to be considered in addition to the provided information.
AN3728: Media Compatibility for IPS PRT Pressure Sensors
http://cache.freescale.com/files/sensors/doc/app_note/AN3728.pdf?fsrch=1&sr=1
For further information, and more details, I would like refer to the "Quality and Reliability" at DL200 Data Library at pages 1-3 to 1-13, that is available at our web site via the following URL:
http://www.freescale.com/files/sensors/doc/support_info/DL200.pdf?tid=redDL200
Relevant tests are on page 1-6.
(Please click on Sensor device data book right below Featured Documents on the right side of the menu bar. Please note that the size of the book will require ~25MB).
