3A fixed 12V buck in a TO-263-5
It switches at 52 kHz and comes in a surface-mount TO-263-5 (DDPAK) package with an exposed tab for heat sinking. This is the high-voltage variant of the LM2576 family, rated for input up to 60V, making it a go-to part for industrial and automotive rails that see transients or unregulated battery voltage.
60V input ceiling — what it buys you
The 60V maximum input voltage is the headline spec that separates this part from garden-variety 36V or 40V buck regulators. It lets you drop directly from a 48V telecom bus, a 24V truck system with load-dump spikes, or a multi-cell lead-acid bank without a pre-regulator. The minimum input is 4V, so it also handles a heavily discharged battery bank down to the point where the system browns out. At 52 kHz switching, the external inductor and output capacitor are larger than what a modern 500 kHz part would need, but the low frequency keeps switching losses low and makes the layout forgiving — a real advantage when you are prototyping on a two-layer board or swapping in a field repair.
The TO-263-5 package (DDPAK) has a large copper tab on the bottom — the board layout must connect that tab to a sufficient copper pour to get the thermal performance the datasheet promises. Without it, the 3A output derates fast above 70°C ambient.
Active production — no EOL scramble
The base product number is LM2576, so if you need a different fixed voltage or an adjustable version, the rest of the family shares the same pinout and package.