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AD8222 use for non inverting amplifier?

I am using an AD8222 for a weight scale application. Is it possible to use the 2nd op amp in the AD8222 in a non inverting amplifier configuration? or is this not advised? If it is not advised, then is their a single op amp version of the AD8222? Also, I noticed that the AD8222 on specifies split rails. Does it not work on single supply rails? Or, you could use it, but it is not the best thing to do?

  • Hi Andrew,

    The AD8222 is an instrumentation amplifier that amplify differential inputs and produce an output with respect to a reference terminal (REF pin). Its transfer function looks like this: VOUT = (VINP - VINN)*Gain + VREF. This shows that a positive differential input will produce a positive output with respect to reference pin and vice versa. The reference pin can also be used to level shift the output as shown on the transfer function.

    Instrumentation amplifier is typically used for weighing scale application or wheatstone bridge configuration due to its high rejection of common mode voltage and excellent DC specs performance. Just a note that AD8222 is a dual channel inamp and we also have a lot of single channel inamp just in case you only need one on your application. AD8222 can work in single supply operation as mentioned on its datasheet.

    What is your intended supply voltage and what is the expected input range coming from your sensor?

    Best regards,