3V fixed LDO, 150 mA, 4 µA Iq — the rail for always-on blocks
The BH30PB1WHFV-TR is a 150 mA fixed-output LDO from ROHM, delivering a regulated 3 V rail from a maximum 5.5 V input. The 4 µA quiescent current makes it a candidate for battery-powered or always-on domains where the regulator's own draw must stay below the system sleep budget. Dropout voltage is 0.6 V maximum at the full 150 mA load — the input rail needs at least 3.6 V to hold regulation across the output current range.
PSRR and noise rejection in the signal chain
Power-supply rejection ratio is 60 dB at 1 kHz — this attenuates switching ripple from a preceding DC-DC converter by a factor of 1000 at that frequency. Above 1 kHz the PSRR rolls off — the typical curve in the datasheet (page 7 of the BH30PB1WHFV series) shows rejection dropping to around 30 dB at 100 kHz. Upstream switching noise above 100 kHz passes through unless filtered ahead of the LDO input.
Package, footprint, and board integration
The BH30PB1WHFV-TR is supplied in a SOT-665 package, also designated 5-HVSOF. The enable pin (Control Features: Enable) allows the output to be gated by a logic-level signal, reducing the quiescent current to near zero when the rail is not needed. Protection features include over-current, over-temperature, and soft-start — the soft-start limits inrush current into the output capacitor during power-up.