Fixed 2.85 V rail with 75 dB ripple rejection
The MIC5205-2.85BM5 TR is a 150 mA low-noise LDO regulator from Micrel with a fixed 2.85 V output. Its 75 dB PSRR at 100 Hz makes it a clean choice for powering analog and RF circuitry where a switching regulator's ripple would couple into the signal path.
Dropout and headroom — 0.35 V at full load
Maximum dropout voltage is 0.35 V at 150 mA output. That means the input rail must stay above 3.2 V to hold the 2.85 V output in regulation. Quiescent current is 150 µA typical, rising to 2.5 mA max under all conditions. The enable pin lets you shut the regulator down for power savings in battery-operated gear.
Temperature range and protection
On-chip protection includes over-current, over-temperature, and reverse polarity — the sort of safeguards that keep a board from dying when a supply rail gets swapped or a load shorts.
Housed in a 5-pin SOT-23-5 (SC-74A, SOT-753), the part is a surface-mount drop-in for compact layouts. The enable pin is on the same side as the output, so the routing for a power-good or shutdown signal is short. No exposed pad — thermal performance depends on the copper area on the PCB.
No official second-source cross-reference is published, so treat it as a single-source BOM line unless you qualify a pin-compatible alternative.