AD8290 : need some inquiries.

Hi,

I'm using the AD8290 to monitor the temperature given by a Pt100 RTD.

I have a couple of question regarding this device :

1 - On page 3 of the datasheet related to the specs, the INPUT row specifies the Input Voltage Range min & max values. Should it be understood as the differential Input Voltage Range values?

2 - On page 18, I have some trouble interpreting the calculation results printed in table 10 about the Input Voltage Min and Max, and the Output Voltage Min and Max.

Computing myself the values with the data given in table 8, 9, and the beginning of table 10 didn't gave me the same results.

So what would be the literal equations leading to the correct calculus?

Michel

  • 0
    •  Analog Employees 
    on Mar 18, 2013 5:21 PM

    Hi-

    I moved this question about the AD8290 to the Instrumentation Amplifiers community.  Someone here should be able to assist you.

    Regards,

    AndyR

    EngineerZone Support Community Manager

  • 0
    •  Analog Employees 
    on Mar 19, 2013 6:06 PM

    Hi Michel,

    Thanks for considering ADI products on your application. Here's my answer for your question.

    1. The IVR specified on the datasheet is not a differential input voltage (Vin+ -  Vin-). It is a voltage that you can apply to both pins (Vin+ and Vin-) with respect to ground.

    2. Please see the picture below on how the parameter is calculated.

    If you have any other concerns, just let us know.

    Best Regards,

    Emman

  • Emman,

    OK everything is clear now, the correct definition avoids a miss-interpretation of the IVR.

    For the ouput min and max, forgot to check the min and max offsets (shame on me, was using only the nominal value).

    Thx a lot for your help.

    Michel