What this part is and where it fits
The Maxim MAX981ESA+ is a single comparator with an on-chip voltage reference, packed in an 8-SOIC surface-mount package. It gives you a clean, pre-set threshold without needing an external reference diode or resistor divider — handy for battery monitors, over-voltage/under-voltage detect, or window comparators on a tight board. The 50mV hysteresis keeps the output from chattering near the trip point, which saves a firmware debounce timer. Temperature grade is -40°C to 85°C, which covers most industrial and automotive-cabin environments. The 80dB CMRR and 80dB PSRR mean the trip point stays put even when your supply is noisy or the common-mode voltage drifts — useful in motor-drive or power-supply feedback loops.
Sourcing and lifecycle — no LTB worry here
No last-time-buy, no end-of-life notice to track. ROHS3 compliant, so it passes the green board requirements without a waiver.
What the ratings mean for your BOM
The 50mV hysteresis is baked in — no external positive feedback resistor needed. That saves two passives and one PCB via per comparator channel. In a high-volume board, that is real BOM cost and placement time. Input offset voltage is 10mV max at 5V supply.
Integration note — field-swap friendly
8-SOIC, 0.154-inch body width, surface mount. No hot-air station required; a standard soldering iron and tweezers will do the swap on a rework bench. Just watch the quiescent draw if you are replacing a different comparator: at 4µA max, it is one of the lighter loads on the rail.