Single comparator with latch — 25 ns decision time for 5 V logic systems
The Maxim Integrated MAX9109ESA+ is a single, high-speed comparator with a latch input, designed for 5 V single-supply systems. Its 25 ns max propagation delay lets it resolve input differences fast enough for PWM loop feedback, overcurrent detection, and zero-crossing circuits in motor drives and power converters. The built-in 2 mV hysteresis eliminates output chatter on slow edges without external positive feedback resistors — saves two passives and their board area. Outputs are TTL-compatible, so it drives 5 V logic inputs directly. Quiescent current maxes out at 700 µA, which keeps the thermal budget low in a dense 8-SOIC layout. The industrial temperature range (-40°C to 85°C) covers factory-floor panels, outdoor telecom gear, and under-hood electronics that don't need full mil-spec qualification.
Supply range and rejection — designed for a regulated 5 V rail
Input bias current is 0.125 µA max at 5 V, and input offset voltage is 1.6 mV max — both tight enough for precision threshold sensing without trimming. The latch input holds the output state when asserted, useful for sampling a fast event and holding it for a slow controller read.