Dual differential comparator with wide supply range
The Texas Instruments LM2903QD is a dual differential comparator in an 8-SOIC package, rated for a supply range of 2 V to 36 V (or ±1 V to ±18 V split supplies). That wide operating window means it can sit on a 5 V logic rail or a 24 V industrial bus without a separate regulator — one less part on the BOM. If this comparator is on a board that sees a hot engine bay or a cold start, the LM2903QD holds its offset and bias specs across that span.
Output flexibility and input characteristics
The output stage supports CMOS, MOS, open-drain, or TTL logic levels — the same device can drive a microcontroller GPIO, a MOSFET gate, or a relay coil through a pull-up resistor. The 20 mA typical output current is enough to sink a small relay or an optocoupler LED directly. For a threshold-detect circuit comparing a sensor voltage against a reference, that offset sets the error floor — budget it into the trip point tolerance. Quiescent current maxes at 2.5 mA per device. In a battery-powered monitor that runs continuously, that draw is modest; in a sleep-wake application, the comparator itself isn't the power hog — the pull-up resistor on the open-drain output often dominates.
Active production and compliance
The pad layout is the same as the LM393, LM339, and LM2903 variants — a board already laid out for any of those accepts the LM2903QD without a spin.