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ltc2495 COM impedance

Category: Datasheet/Specs
Product Number: LTC2495

What is the input impedance (or drive requirements) for the COM input?  Can I connect this to Vref/2 in order to get full range on my single ended inputs?  If I ground COM and REF- then my single ended inputs have a full scale value of only Vref/2.

Thread Notes

  • Hello  , 

    The COM input impedance is the same as other analog inputs, as these "see" the same ADC input through the multiplexer. You certainly can connect a mid-supply VREF through COM, just make sure that the source impedance will be lower than 10k ohms to ensure proper settling.

    If you are experiencing accuracy issues due to input voltage not settling right, you may use an external buffer as shown below.