Ultra-low-power comparator for battery-edge threshold detection
The Analog Devices MAX919ESA+ is a single general-purpose comparator from the Beyond-the-Rails™ series, drawing just 1.2 µA quiescent maximum — a fit for battery-powered sensor nodes, threshold monitors, and wake-up circuits where every microamp counts. The CMOS push-pull rail-to-rail output drives logic inputs directly — no external pull-up resistor, which saves board space and one BOM line.
Hysteresis and propagation delay — what they mean for the threshold decision
Built-in 4 mV hysteresis prevents output chatter when the input signal crosses the threshold slowly — a thermistor voltage or a ramp from a current-sense amplifier will not trigger multiple edges. Maximum propagation delay is 940 µs — the comparator takes under a millisecond to change state. For a battery-protection circuit or a slow over-temperature latch this is ample; for a high-speed PWM or zero-crossing detector it is the ceiling that limits the switching frequency.
Active lifecycle and compliance posture
ROHS3 compliant, with a CMRR of 66.02 dB typical and PSRR of 80 dB typical — the supply-rejection figure means the threshold stays stable even when the battery voltage droops under load.