Hi! I bought a 20-Inch-G-4V sensor and I had a question : what is its technology? By technology, I mean is it a piezoresistive sensor, piezoelectric sensor or a capacitive pressure sensor ? Thanks!
The precise technology used in this sensor is not specified, other than the datasheet’s mention of a “proprietary” technology and “…silicon, micromachined…” internal element. This would suggest to me that some manner of MEMS strain gauge might be incorporated, but I cannot state this as fact.
The sensing technology that is used would be a piezo resistive.
Per the Manufacturer:
"This is a solid diaphragm sensor utilizing our proprietary low pressure C0-Beam pressure die with 4 strain gauges diffused into the silicon diaphragm. They are connected in a Wheatstone bridge circuit. Voltage is applied at 2 nodes and a millivolt signal is measured at the other two points. Strain gages act like a water hose- if you stretch them and reduce the diameter- the resistance value goes up. If you compress them and increase the diameter then the resistance goes down. "
The device has two pressure dies next to each-other on the wafer so that they can have the same chemistry and sensitivity. Both Electrically and pneumatically cross-coupled to cancel out most of the common mode errors making the zero offset value more stable than single die sensors with changes in time, temperature and humidity.
An internal ASIC is used to store the calibration points and amplify the signal to a 4V span.
A few white papers available for more detail.
DS-0287-Rev-A1-1 low pressure die.pdf (123.0 KB)
Dual Die Compensation.pdf (183.0 KB)
Pressure types WP-0001_Rev_A.pdf (149.1 KB)
WP-0002_Rev_A Pressure Point 1 Measurement Types.pdf (148.9 KB)
WP-0011_Rev_A DP to Flow paper.pdf (210.6 KB)
DS-0368_Low P .25 60 IN 4V Rev_A.PDF (595.9 KB)
Let me know if you have any further questions.