Differential comparator with flexible output stage
The Texas Instruments LP311D is a single-element differential comparator in an 8-SOIC package. Its open-collector and open-emitter output stage lets you wire outputs in a wired-OR configuration or shift logic levels to a different supply rail — useful when the comparator output must drive a load referenced to a voltage other than its own supply. Supply range covers 3.5 V to 30 V on a single rail, or ±1.75 V to ±15 V with dual supplies. Quiescent current maxes at 300 µA — not a micropower part, but low enough for line-powered or intermittently battery-backed boards. Input bias current is 0.1 µA maximum at ±15 V, and input offset voltage is 7.5 mV maximum at ±15 V.
This limits the LP311D to indoor, controlled environments — office equipment, bench instruments, appliance control boards, and similar settings where the ambient temperature stays within that window.
ROHS3 compliant.
Sourcing reality
An active, widely used comparator in a standard SOIC-8 footprint. No single-source risk — multiple channels carry this part.