Hi! I would like to know a few thing about an application that requires the use of the AD620 for amplifying signals from a full- wheatstone bridge with strain gauges.
I am using 350Ohms Strain gauges connected to the AD620 like shown in the photo. Also, I am driving the Ref Pin to a mid-voltage using a buffer, as required by the IC. In my board, there are a total of 4 AD620 (so it is possible to use 4 force sensors.). Can I use the output of the same LM358 to drive the Ref Pin in all AD620 chips? Or should I use one OpAmp for each sensor? The offset level should be the same for each w-bridge.
Also, should I use any resistor between the signal from the bridge and the AD620 inputs?
The VCC is 3v3 and this circuit is replicated 4 times in my current design. If it is possible to use only one LM358 for every AD620, it would significantly reduce my board design size.