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ADA4945 Differential Input Voltage

Product Number: ADA4945

In the datasheet of the DA, under the absolute maximum ratings table it is mentioned that the differential Input Voltage shall not exceed +/- 1 Volt.

What this practically means for the maximum input voltage applied at the input?

What if the operation of the DA is configured for conversion of a single ended and unipolar signal to a differential unipolar signal?

I cannot apply a single ended input voltage of 5Vpp assuming a power supply of P7V5 and N2V5?



Image added for clarity.
[edited by: elsiesemico at 4:20 PM (GMT -4) on 3 Nov 2023]
  • Hi,

    We get this question a lot and I understand the confusion. People are getting confused with the input voltage range and input differential voltage.
    Differential input voltage is the difference of the voltage directly at the input pin of the part, which are rarely too far to each other due to the feedback loop which holds it at zero volts(neglecting the offset voltage).

    However some conditions like a very fast input signal(slew rate limitation) and power up, the input may be subjected to differential voltage which is not zero.

    Certain input structures require limiting of differential input voltage to prevent damage. These op amps will generally have internal back-to-back diodes across the inputs.
    You can refer to the picture you attached that the inputs(voltage source before Rg) are large and VinP has an input of 5Vpp, yet Vp and Vn which the differential input voltage is, is held at zero.

    Regards,

    Goz