Real Op-Amp Limitations

Offset voltage, bias current, gain-bandwidth product, slew rate and output swing.

Intermediate

Input offset voltage $V_{OS}$ — a small error multiplied by the noise gain.
Input bias current — flows into the inputs and creates errors in large resistors.
Gain–bandwidth product (GBW) — closed-loop bandwidth ≈ GBW / gain. A 1 MHz op-amp at gain 100 has ~10 kHz bandwidth.
Slew rate — maximum output rate of change (V/µs). Full-power bandwidth: $f_{max} = \dfrac{SR}{2\pi V_p}$ .
Output swing — non rail-to-rail op-amps (LM358 output can't reach $V_{CC}$ ) lose 1.5 V or more near the supply rails.
CMRR and PSRR — rejection of common-mode and supply changes.

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