Basic requirements in the design and manufacturing of pressure sensors for automotive applications ensure optimal performance in the range of temperature, vibration, media, shock, and electromagnetic conditions the sensor must endure to perform vital functions. Harsh environments require enhanced protection of the sensor's electrical structures against the pressurized medium. SMI’s pressure sensors are produced using total quality management in a fab certified to be conformant with ISO/TS 16949 automotive standards.

Minimum operating temperature	–40°C
Maximum operating temperature
Passenger compartment	85°C
Chassis/wheel	125°C
Under the hood	>140°C
Static acceleration	>2000 g (for TPMS applications)
Dynamic acceleration (shock)	>5000 g (for TPMS applications)
Vibration	20 Hz–2 kHz (over extended time period)
Chemical resistance	To all kinds of liquids present in an automobile environment, including the workshop: fuels, oils, brake fluids, cleaners, waters, salt water

To this end, the piezoresistive bridge on the micromachined silicon membrane typically is not exposed directly to the environment in which it operates. Instead, protective silicone-gel coatings, or caps, form a barrier between the sensor's front side and harsh environments, such as those involved in MAP and BAP applications (Figure 3). Field shields and noble metals are also used to protect the sensor's electrical structures against pressurized media. The idea is to protect the sensor's front side from the medium and leave only the silicon backside exposed to the harsh environment. This approach is used widely in tire pressure monitors and MAP sensors.