2 A adjustable buck for 12 V / 24 V industrial rails
The STMicroelectronics L5972D is a 2 A adjustable step-down (buck) switching regulator in an 8-SOIC package, designed for positive-output voltage conversion from unregulated supplies up to 36 V. Its 250 kHz fixed switching frequency keeps the inductor small enough for compact layouts while staying out of the AM band and avoiding the switching-loss penalty of 1 MHz+ parts. The output is adjustable from a 1.235 V reference up to 35 V, covering the common 3.3 V, 5 V, and 12 V rails from a 24 V industrial bus or a 12 V automotive battery line.
Junction temperature and thermal design
Rated for a junction temperature range of -40 °C to 150 °C, the L5972D can operate in under-hood automotive, factory-floor enclosures, or outdoor telecom cabinets where ambient temperatures hit 85 °C or higher. At 2 A continuous output, the thermal pad on the 8-SOIC package must be soldered to a sufficient copper area on the PCB — a via-stitched ground plane pour is the standard approach to keep the junction below the thermal shutdown threshold. The wide temperature range also means the part can handle transient load dumps and high-side ambient without derating the output current, as long as the board-level thermal resistance is managed.
Sourcing and lifecycle
The L5972D carries an Active lifecycle status per the manufacturer, with ROHS3 compliance.