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ADA4950-2 Input Current Specification

Hi,

I am using ADA4950-2 Differential Amplifier to make  differential my DC signal. I hve a output common mode voltage of 1.5 V for this chip
I have two questions:

1) When nothing is connected to INA- and 1.65 V is connected to INA+ I see 1.47 V(apporixmately output common mode voltage) at INA- pin. What could be the reason for this?

2) I have a system with 1.65V -2.65 V changing DC level input for 1.5 V common mode voltage in this chip? What will be the input current for this sitiuation?( (Vin-Vocm)/500 ohm is a suitable approximation???)

  • Hello.

    The voltage differences does not depend mainly with the input bias current for the contribution would be minimal. Please attach your schematic. The readings would vary depending how you measure it as well as how you implemented the Differential amplifier. Also on this setup, you won't expect the outputs symmetrical due to imbalances in the input.

    Regards,

    Jino

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