piezoceramic

[hkm]

Hi All

I want to use piezo sensor as below link, but unable to determine the correct instrumentation.  I hope anybody  that used this type of sensor before can give me some advice. I also attach the sensor spec in jpeg format.

http://www.piezo.com/tech2intropiezotrans.html

Thank you

best regards

HKM

[Henrik_Volkers]

I never used that sensor, but work a lot with piezo effect based accelerometers.

The piezo will create a charge q based on the strain/stress/force applied.

On the same time this sensor is a capacitor C with your electrodes as plates and the piezo ceramic as the dielectric material.

The charge together with the capacitor will result in a voltage U.

Formula:  q=C*U

Now you have two opportunities: 

Measure the voltage or measure the charge.

Voltage: Need a very high impedance,  is influenced by parasitic cable capacity.So look at the specs and get one with an input impedance in the G ohm range.

Charge: need a transimpedance (or charge) amplifier (extra circuitry) and than work with every voltage input. Is not affected by cable capacity.

More in this appnote http://focus.ti.com/lit/an/slyt369/slyt369.pdf