What is the difference between a single supply op-amp and a dual supply op-amp?
Generally, “single supply op amp” means the op-amp has an input common mode range that includes V- (Gnd). However, since there is no “ground” pin on an op-amp, there may no difference in the actual circuitry, layout, or behavior of op-amp itself that allows it to operate on a single supply vs a dual or split supply. The only difference one might find upon a thorough examination is in the op-amp data sheet. An op-amp that is designated as a dual supply op-amp usually references the output load with respect to ground, whereas a single supply op-amp usually references the output load with respect to the midpoint voltage of the single supply. Although op-amps that are designated as single supply op-amps generally operate at lower voltages, this is not a requirement. So whether you operate your op-amp from a single 5 volt supply and ground, or from +2.5 and -2.5 volts, makes no difference to the op-amp. All the op-amp cares about are the relative voltages of those supplies with respect to e
