Noise rejection and dropout — the two numbers that matter
The BH28PB1WHFV-TR is a fixed 2.8V LDO regulator from ROHM, delivering up to 150 mA from a 5.5V max input rail. The 0.6V dropout at full load sets the minimum headroom: feed it 3.4V minimum to hold regulation at 150 mA. Quiescent current sits at 4 µA typical, which matters for battery-powered gear that spends most of its life in a low-power state — the regulator's own draw won't dominate the sleep budget. The enable pin lets a GPIO or supervisor shut the output down entirely, cutting supply current to near zero when the downstream load is idle.
Package and board-fit for tight layouts
Housed in a SOT-665 (also called 5-HVSOF) surface-mount package, the BH28PB1WHFV-TR occupies minimal board area — roughly 1.6 mm x 1.6 mm with five leads. The small footprint suits wearable, IoT, and portable devices where PCB real estate is at a premium. Mounting is standard SMD reflow; no exposed pad, so thermal dissipation relies on the copper traces and via array under the package.