AD9286 with AD9286-500EBZ

Hello all,

I am currently looking for a evaluation board for data acquisition. It should contain a high-speed bipolar ADC.

The AD9286 (500 MSps, 8 Bit) seems to hit my requirements. It has a differential input with full scale voltage of 1.2 Vpp. Can I use this ADC in a bipolar way (offset binary, -600mV to 600mv) ? I would need to cover both negative and positive inputs.

Thank you very much for your support!

MattiJo

  • 0
    •  Analog Employees 
    on Feb 15, 2016 8:00 PM

    Hi Mattijo,

    The AD9286 will accept a differential input of +/-600mVpp.  This means that each ADC input Vinx+ and Vinx- can accept an input with a peak voltage of 300mV (each ADC input would be a peak to peak of 600mV).  The input of the device is biased to a common mode of 1.4V.  This means that the maximum voltage on the ADC input is 1.7V which has sufficient headroom on the 1.8V supply (on the lower side the voltage would go down to 0.9V which is once again sufficient headroom but in this case headroom above GND).  The total differential voltage is (600mVpp on Vinx+) - (-600mVpp on Vinx-) = 1.2Vpp.

    I am assuming you are taking care of the necessary common mode by using DC blocking capacitors as is done on the evaluation board for a passive input.  If using an amplifier to drive the ADC, given common mode compatibility you can DC couple letting the amplifier set the common mode to be compatible to the ADC common mode of 1.4V.

    The output data format can be set to offset binary.  I am assuming this is what you are asking.

    Please let me know if you have further questions.

    Regards,

    Jonathan