What this automotive LED controller brings to the bench
The MAX25601BAUI/V+ is a DC DC controller for automotive LED lighting, supporting step-down (buck) and step-up (boost) topologies.
Temperature range and what it means for the BOM
Rated -40°C to 125°C, this controller lives in the engine bay or behind the headlamp assembly without derating. That 125°C ceiling covers the ambient under the hood on a hot day with the engine running — the kind of environment that kills a commercial-grade part in one summer. The 28-TSSOP with exposed pad needs a thermal via array under the pad to pull heat into the PCB copper; skip that and the junction temperature climbs faster than the datasheet curve predicts. For a BOM freeze, this part is active — no LTB watch, no PCN-driven scramble for a last-time buy.
Internal switches and output regulation
Internal switches are on-die, so the bill of materials stays tight — no external MOSFET pair to source and qualify. The regulated output sits at 4.9 V to 5.1 V, which is the typical voltage for powering the LED string sense circuitry or a local microcontroller. Two outputs mean you can run separate LED loads with independent dimming profiles; the analog dimming path gives continuous current adjustment, while the PWM path lets you hit deep dimming ratios without colour shift.