3V fixed LDO for low-power rails
The STMicroelectronics LD2980ABM30TR is a single-output positive fixed LDO regulator delivering a regulated 3 V output at up to 50 mA. Key protection features include over-current and over-temperature shutdown, and an enable pin allows external on/off control for sequencing or power-saving modes.
The maximum dropout voltage is 0.225 V at the full 50 mA load. That means a 3.3 V input rail can hold the 3 V output through a cold-crank dip down to about 3.225 V before the regulator drops out. PSRR is specified at 63 dB at 1 kHz, which is adequate for cleaning up switching-regulator ripple in the audio band. If your load demands higher rejection at higher frequencies (e.g., 100 kHz ripple from a DC-DC converter), consider a part with a wider PSRR bandwidth — the LD39020DTPU33R offers 80 dB to 55 dB from 1 kHz to 100 kHz.
Active, ROHS3, and ready for production BOMs
For dual-sourcing flexibility, the LD39020DTPU33R is a functional alternative in the same SOT-23-5 footprint but with a 3.3 V fixed output and 200 mA capability. Verify the output voltage and current requirements before substituting.