Problem using AD8629 as an ADC driver

I wanted a low drift ADC driver in a precision thermometer circuit so I used an AD8629 (please refer to attached pdf). The op-amp +ve input was fine (i.e. a dc level proportional to the thermistor resistance) but the output was oscillating at several hundred mV, at about 800kHz. The same thing happened using an LTC2052, but problem was fixed when I used an LMP7702. What was I doing wrong?

ADCDriverProblem.PDF
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    •  Analog Employees 
    on Aug 2, 2018 3:00 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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  • 0
    •  Analog Employees 
    on Aug 2, 2018 3:00 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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