An op amp with the correct supply voltage is not automatically suitable for your signal. The input may exceed its common-mode range, the output may not reach the required voltage, or the signal may change faster than the amplifier can follow.
Check these eight points
- Supply: verify single or split supply and the permitted minimum and maximum.
- Input range: compare the complete input signal with the specified common-mode range.
- Output swing: check how close the output gets to either rail at your actual load.
- Gain and stability: confirm stability at the intended closed-loop gain.
- Bandwidth: determine the required gain-bandwidth at the actual gain.
- Slew rate: check whether large or fast signals can be followed without slew-rate limiting.
- Accuracy: assess offset, drift, bias current and noise for the source impedance.
- Load and package: verify output current, capacitive load, channel count, package and temperature.
Rail-to-rail input and rail-to-rail output are separate properties. Even a rail-to-rail
output usually keeps some distance from the supply rails; the amount depends on current, supply
and temperature. Use the tables and curves for the exact device.
Define supply, signal range, gain, frequency, accuracy and load first. Then search for operational amplifiers and compare the complete specifications and package before ordering.