4V to 42V input, 100mA output — the Himalaya workhorse for wide-VIN rails
The MAX17532ATB+T is a step-down (buck) switching regulator from Analog Devices' Himalaya series, designed to deliver up to 100 mA from a 4 V to 42 V input rail. That input range covers everything from a 5 V logic rail to a 36 V industrial bus or a 48 V telecom supply with margin — the 42 V abs-max lets it survive load-dump transients without an external clamp.
Adjustable output from 0.8 V to 37.8 V — one BOM line for multiple post-rail voltages
The output is adjustable via an external resistor divider from a 0.8 V reference up to 37.8 V. Lower frequencies give better efficiency at light load; higher frequencies shrink the inductor and output capacitor but increase switching losses. The 2.2 MHz ceiling keeps the converter above the AM band and lets the magnetics fit in a small 0603 footprint. Synchronous rectification is built in — the low-side FET replaces the external Schottky diode, which cuts rectifier losses by roughly 5-10% at full load and keeps the board cooler. No external catch diode to budget for.
10-TDFN (3x2) with exposed pad — the layout engineer's thermal checklist
Without that thermal relief, the junction-to-ambient thermal resistance climbs above the 125 °C-rated operating temperature at full load in a 85 °C ambient. The 3x2 mm body is a tight fit for a 42 V-capable regulator — the high-side FET's Rds(on) is sized for 100 mA, not for heavy loads, so the die stays cool even with the small paddle. The pinout is single-output positive, with the feedback pin adjacent to the output and the enable pin on the opposite side for clean routing separation.