12V fixed output, 1A — the BOM-fit check
The Texas Instruments LM2940CT-12 is a fixed 12V output, positive-voltage LDO regulator rated for 1A continuous output current. The 0.8V maximum dropout at full load means the input rail needs at least 12.8V to maintain regulation — a 13.8V nominal supply (common in automotive and industrial 12V bus systems) provides adequate headroom.
At 1A output the quiescent current is 10 mA typical, rising to 15 mA maximum — the LDO stays efficient enough for moderate-load designs without a heatsink, though the TO-220-3 tab can be bolted to a ground plane or chassis for thermal relief.
For new designs, look at the pin-compatible LM2940T-12.0 or the LM2940S-12 (TO-263 surface-mount variant) — both are active and share the same 12V fixed output and 1A rating.
TO-220-3 — through-hole mounting and thermal path
The TO-220-3 through-hole package (supplier device package TO-220-3) is a standard three-lead power package. The metal tab is internally connected to the output pin; it can be soldered to a copper pad on the PCB or bolted to a heatsink.
Protection features — built-in fault tolerance
The LM2940CT-12 integrates over-current, over-temperature, reverse polarity, and short-circuit protection. These make it a robust choice for power supplies in automotive aftermarket, industrial control panels, and bench power supplies where the load may fault or the input polarity could be reversed during wiring.