Operational amplifiers are the most fundamental amplification and conditioning devices in analog signal chains, used for amplification, filtering, comparison and computation circuits across sensor signal processing, instrumentation and industrial control; offset voltage and temperature drift set the accuracy ceiling, while Iq and noise typically trade off against each other.
How to read the key parameters:
- Gain-bandwidth product (GBW): The lineup covers 0.01MHz to 10MHz — higher values handle a higher signal-frequency ceiling but typically draw more quiescent current. As a rule of thumb, GBW should exceed the signal's highest frequency by 5~10x to leave adequate gain margin.
- Quiescent current (Iq): The lineup spans a wide 0.5μA to 1100μA, the classic power-vs-speed trade-off in op-amp selection — low-Iq parts save power but usually have lower slew rate and GBW; high-Iq parts respond faster at higher power cost.
- Offset voltage (VOS): The lineup ranges from about 0.01mV up to 5mV, setting the DC-accuracy ceiling. Precision measurement and sensor conditioning should use low-VOS tiers; general conditioning that's accuracy-insensitive can use general-purpose tiers at lower cost.
- Slew rate (SR): The lineup covers 0.25V/μs to 14.5V/μs, setting the maximum rate of output-swing change. Insufficient SR distorts the output when driving square waves, pulses or large high-frequency swings — estimate the floor from your max swing and frequency.
- Supply voltage: Low-voltage parts at 1.7~5.5V suit battery supplies; wide-voltage parts at 3~36V connect directly to industrial 12V/24V rails without extra regulation. Wide-voltage Iq is mostly in the low hundreds of μA, but some low-voltage parts draw even more — check each part's actual Iq.
Three steps to select:
- Estimate the GBW floor from signal frequency and gain, then bound Iq by the power budget.
- Set the VOS tier by accuracy requirement, then check SR against swing and frequency needs.
- Select the voltage tier by system supply, then finalize the part by channel count and package.
Common pitfalls:
- Looking only at open-loop GBW while ignoring that closed-loop bandwidth falls with gain (closed-loop BW ≈ GBW/gain) — high-gain applications easily run bandwidth-short.
- Chasing the lowest Iq without noting that SR and GBW usually drop in tandem, leaving response speed short of actual needs.
- Mismatching supply-voltage range and rail-to-rail input/output capability — a wide-voltage part in a low-voltage system wastes usable swing.
Filter and compare part numbers by GBW, Iq, VOS and supply voltage in our online selector; contact us for support on a specific signal chain.