Unity gain op-amp buffer, single supply - potential problems?
Common mode voltage range could be an issue:



With power supply at 5V you are left with a max common mode voltage of 3.5V. In non-inverting configuration the inverting input will sit at about 2.5V so you only have 1V headroom. If your supply lowers just a bit you risk malfunctioning. And even if it stays stiff at 5V, note that those specs are given with an \$R_L=10k\Omega\$ (see above the table). So if you use the opamp as a buffer your load could have lower resistance and this could impact the max common mode voltage tolerated by the opamp.