reference of AD9245

We use AD9245 to sample the signal detect single end amplifier with output voltage from 0 to 2 volts.  We connect this output to Vin+. My question is that should we connect the Vin- to ground or to a voltage reference of 1 volt. If we connect the Vin- to ground, the differential input of AD9245 will be from 0 to 2 volts. If we connect the Vin- to 1 volt reference,  the differential input of AD9245 will be from -1 to 1 volt.  Could you please tell us which solution is right or both are right?

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    •  Analog Employees 
    on Dec 12, 2017 6:08 PM

    Hello,

    For a 2 V input single-ended input span ranging from 0 to +2 V, the VREF output must be configured for 1 V while the VIN- pin is connected to VREF via the same value resistor (i.e. 33 ohms) that is used to connect VIN+ to the amplifier source which is producing the 0 to 2 V input signal.

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  • 0
    •  Analog Employees 
    on Dec 12, 2017 6:08 PM

    Hello,

    For a 2 V input single-ended input span ranging from 0 to +2 V, the VREF output must be configured for 1 V while the VIN- pin is connected to VREF via the same value resistor (i.e. 33 ohms) that is used to connect VIN+ to the amplifier source which is producing the 0 to 2 V input signal.

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