Fixed 5V LDO for low-power rails
The LP2980AIM5-5.0 is a fixed 5V positive-output LDO from Texas Instruments, delivering up to 50 mA. It is designed for applications where a clean, regulated 5V rail is needed from a higher input voltage up to 16V. The low dropout of 0.22V max at 50 mA means the input can sit as low as 5.22V and still maintain regulation — useful in battery-powered or post-switcher rails where headroom is tight.
63 dB PSRR at 1 kHz — ripple rejection in noisy environments
With a PSRR of 63 dB at 1 kHz, this LDO attenuates input ripple by a factor of roughly 1400× at that frequency. For a 100 mVpp ripple on the input, the output sees under 100 µVpp — clean enough to bias a sensitive analog front-end or a reference buffer. The quiescent current is 95 µA typical, so the ripple rejection comes without a heavy idle-current penalty.
Wide temperature range and protection set
On-chip protection includes over-current, over-temperature, and short-circuit — the regulator survives a sustained output short without damage. The enable pin allows external on/off control, reducing quiescent draw to near zero when the rail is not needed.
NRND — plan a replacement now
The part is still available through independent distribution for existing BOM lines, but new designs should select a current-production alternative. The SOT-23-5 footprint is common — many 50 mA LDOs in this package are drop-in candidates, but pinout and enable polarity must be verified against the existing layout.