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I'm planning to buffer a 0-10V DC signal coming from a potentiometer windvane.
I want to use this opamp for the purpose and the opamp will be powered as single supply with 12V Vcc.
Can I use this opamp for 0-10V inputs as a buffer aka unity gain? I'm worried about CMRR issues and Im not able to interpret that for this scenario.
Alternatively I have this opamp as well.
It should be fine for a non-precision application such as a windvane potentiometer. Your actual application circuit (please edit the question and add this information to the question) shows an input that goes from about 100mV to the excitation voltage minus 100mV. The amplifier you are looking at can even sink a bit of current at that minimum output voltage (typically as much as 2mA according to figure 6).
You could probably use a much cheaper single supply op-amp instead. You may find that a bipolar type is easier to protect, although with a CMOS type you can add a large value resistor to the input without unduly affecting accuracy (much higher than the 1K shown). The absolute maximum 15.5V supply voltage is a bit closer than one might like to 12V.
The datasheet will tell you what voltages the input and output can support. As expected for an opamp advertized as "Rail-to-Rail Input and Output", the specifications for VCM and VO show that you can go almost to the rails.
Typical CMRR is specified as 82 dB. Any dB calculator shows that −82 dB corresponds to an amplitude ratio of 0.0000794, so a common-mode change of 10 V at the input, attenuated by 82 dB, would result in a 794 µV change at the output. However, worst-case 60 dB corresponds to 10 mV.
