Low-dropout regulator with wideband PSRR — what the numbers mean for your rail
The MAX8902BATA+T is an adjustable positive LDO from Analog Devices, delivering up to 500 mA with a maximum dropout voltage of just 0.12 V at full load — meaning a 3.3 V input rail only needs to stay above 3.42 V to keep the output in regulation. Its PSRR profile — 92 dB at 5 kHz rolling off to 62 dB at 100 kHz — tells you where the regulator suppresses upstream switching noise: the high 5 kHz rejection cleans up the fundamental and first harmonics of a 500 kHz buck converter, while the 100 kHz figure still provides 30 dB of attenuation at the switching edge. Output is adjustable from 0.6 V to 5.3 V via an external resistor divider, covering core voltages for low-power MCUs, RF transceivers, and sensor analog supplies.
Package, thermal path, and board-level fit
Surface-mount assembly with a 0.50 mm pitch; the exposed pad is the primary thermal and electrical ground connection.
Quiescent current, supply current, and always-on system design
Quiescent current is 120 µA typical, with a maximum supply current of 160 µA — low enough that a battery-powered sensor node drawing 50 µA in sleep mode sees the LDO's own consumption dominate the idle budget unless the Enable pin pulls the regulator into shutdown. The Enable and Power Good control features allow sequencing: PG asserts when the output reaches regulation, so a downstream load (FPGA core, ADC reference) can be held in reset until the rail is stable.
Protection coverage and operating range
Built-in protection includes over-temperature shutdown, reverse polarity protection, short-circuit current limiting, and a soft-start ramp that limits inrush into a discharged output capacitor — no external sequencing supervisor needed for basic fault handling.