The STMicroelectronics LM324D is a quad general-purpose operational amplifier in a 14-SOIC package, part of the industry-standard LM324 family that has been a workhorse for signal conditioning, sensor buffering, and active filtering in commercial-temperature designs. Its 1.2 MHz gain-bandwidth product and 0.4 V/µs slew rate define the usable signal bandwidth — for a gain-of-10 stage, the closed-loop bandwidth settles around 120 kHz, which covers most low-frequency analog front-ends such as thermocouple amplifiers, strain-gauge bridges, and 4-20 mA loop receivers. The 3 V to 30 V single-supply (or ±1.5 V to ±15 V dual-supply) range means the same part can run off a 3.3 V regulated rail for battery-powered gear or a 24 V industrial supply without a second regulator — the input common-mode range includes ground in single-supply operation, so it handles 0 V-referenced signals directly. Drawing 1.5 mA quiescent current across all four amplifiers, the LM324D keeps the thermal budget modest in a dense board — at 40 mA per channel output drive, it can swing into a 600 Ω load while staying within the SOIC-14 package's dissipation limits at 70°C ambient.
Sourcing now runs through independent distribution and surplus channels. Each lot is date-code verified and physically inspected — the laser etch on the package top is checked against ST's known marking formats for that assembly plant and week, so the part's provenance traces cleanly before it reaches your reel or tube. The LM324D remains ROHS3 compliant, so it passes the same environmental restrictions as current-production parts — no special handling or exemption paperwork needed for EU or UKCA markets.
Package and board-level fit — SOIC-14 footprint
Supplied in tube packaging — the tubes are antistatic and the parts are oriented pin-1-to-rail, which feeds directly into most through-tube pick-and-place feeders without retooling the tape-pocket setup.