Capacitive MEMS low pressure sensor

Louise Smyth

With the PPCP3 series, Pewatron presents a new generation of pressure sensors based on capacitive technology. The MEMS-based capacitive measuring principle enjoys some considerable advantages over the widespread and well-established piezo-resistive sensors. Tests have shown that one side of the membrane can be loaded with up to 20 bar overpressure, and this in a low pressure sensor with a measurement range of just a few mbar. This represents a ground-breaking advantage over conventional piezo-resistive MEMS pressure sensors. The disruptive technology also stands out for its extremely low power consumption, very high resolution and accuracy.

The sensor chip has two measuring and two reference capacitances, a design that ensures very good offset stability and almost no drift. Unlike complex, double-chip solutions based on the piezo-resistive technology available on the market, the PPCP3 has everything integrated on a single sensor die, making it cheaper and easier to produce.

Capacitive technology has already established itself in applications such as touchscreens or proximity switches, and it has developed rapidly in recent years thanks to its use in the consumer sector. The time has now come for capacitive MEMS pressure sensors – with their technological advantages, Pewatron are set to revolutionise pressure sensor technology in the coming years.