5V fixed LDO — 150 mA, 165 mV dropout, SOT-23-5
The MAX8878EUK50-T: The low-dropout architecture keeps regulation intact with just 165 mV headroom at full load — the input rail can droop to 5.165 V before the output falls out of spec. The fixed 5 V output means no external resistor divider is needed — the output voltage is set internally and the BOM is reduced to the input and output capacitors. An Enable pin (active-high) lets the system power down the regulator when the load is idle, pulling the quiescent current to near zero.
Package and board-fit — SOT-23-5, 0.95 mm pitch
The part is housed in a 5-pin SOT-23-5 (SC-74A) package with a 0.95 mm lead pitch. This is a standard, low-cost surface-mount footprint that routes cleanly on a 2-layer PCB — no micro-vias or blind vias required. The Bulk (tube/tray) packaging suits prototyping and low-volume production; for high-volume reels, order the tape-and-reel variant if available.
Protection and quiescent profile
On-chip protection includes over-current, over-temperature, reverse polarity, and short-circuit — the LDO survives a stalled output or a miswired load without external clamp diodes. Quiescent current is 180 µA typical, and the total supply current (including the pass-element drive) peaks at 100 µA. This is moderate Iq — not a nano-power LDO for always-on coin-cell designs, but acceptable for a 5 V rail that powers a microcontroller or sensor intermittently.