Fixed 2.5V rail for core logic
The MAX1589ETT250+ is a single-output LDO regulator delivering a fixed 2.5V output at up to 500mA — a common core voltage for low-power MCUs, FPGAs, and RF transceivers that need a clean, regulated rail from a 3.3V or 3.6V input bus. Maximum dropout is 350mV at the full 500mA load, meaning the input must stay above 2.85V to keep the output in regulation across the temperature range.
PSRR and noise rejection at 1kHz
With 70dB of power-supply rejection at 1kHz, this LDO attenuates switching ripple from a buck converter or charge pump by a factor of over 3000 — critical for analog front-ends or RF oscillators where supply noise couples into the signal path. The quiescent current is 140µA typical, so the regulator's own draw stays low enough for battery-powered equipment that spends most of its time in idle or sleep mode.
Thermal and protection features
The 6-WDFN package with exposed pad (3x3mm) conducts heat to the PCB ground plane — layout should connect the pad to a copper pour for the rated 500mA at 85°C ambient. Built-in over-temperature and short-circuit protection allow the regulator to survive a sustained output fault without external clamp diodes. Control features include an enable pin for power sequencing and a reset output that holds the load in reset until the output stabilises.
ROHS3 compliant, covering the full ten restricted substances including the four phthalates added in EU Directive 2015/863.