3A fixed 1.5V rail — dropout and headroom
The LMS1587CSX-1.5/NOPB: PSRR is 60 dB to 72 dB at 120 Hz, which attenuates line-frequency ripple from a rectified AC supply by a factor of 1000 to 4000 — useful for powering sensitive analog or mixed-signal loads from an unregulated front-end.
Package and thermal path
Housed in a DDPAK/TO-263-3 (D²Pak) surface-mount package, the LMS1587CSX-1.5/NOPB uses the large copper tab as the primary heat path. Operating temperature range is 0°C to 125°C, suitable for commercial and industrial environments where the ambient stays above freezing. The part includes over-current and over-temperature protection, latching off during fault conditions and auto-recovering when the fault clears.
Quiescent and supply current
Quiescent current is 7 mA typical, and the maximum supply current is 13 mA. For a 3A output, the quiescent loss is about 35 mW at 5V input — negligible in absolute terms but worth noting for always-on rails where every milliwatt counts.