Introduction
The piezo-resistive type sensor is a very common barometric pressure measurement technology. It has many advantages including:
- Simple manufacturing process.
- Have a wide detection range.
- Compact, highly sensitive and have good linearity.
Even good things usually have some disadvantages:
- Sensitive to ambient temperature, mitigated with temperature compensation.
- Power consumption issues can make them unsuitable for battery-operated system.
- Scaling down the size can reduce sensitivity and increase power consumption
- At high temperatures and overpressure situations the adhesives in the package can fail.
How It Works
The piezoresistive effect allows these sensors to convert mechanical stress into electrical signals, enabling accurate pressure readings across different conditions. They are particularly useful in applications where rapid response is essential due to their ability to generate an electric charge in response to changes in pressure.
Piezo-resistive pressure sensors utilize a single Si crystal plate as a diaphragm and diffuses impurities on its surface to form a resistive bridge circuit. Atmospheric pressure distorts this silicon plate causing a resistance change in the resistive bridge.
Barometric pressure can then be very accurately calculated by detecting and measuring this change in resistance.