Fixed 12V rail with 2A headroom
The BAJ2DD0WT is a single-output positive LDO regulator from ROHM, delivering a fixed 12V output at up to 2A continuous. With a 25V maximum input, the part comfortably handles 24V industrial buses and 15V intermediate rails. The 55dB PSRR at 120Hz attenuates ripple from a full-wave rectified mains supply by a factor of about 560 — useful for post-regulation after a switching pre-regulator or a transformer-rectifier stage.
Protection set and quiescent draw
Built-in over-current, over-temperature, and over-voltage protection reduce the external supervision circuitry needed. The 120 µA quiescent current is modest for a 2A LDO — it won't dominate the standby budget in a system that spends most of its time powered. The enable control pin allows the regulator to be gated by a logic signal, shutting down the output and dropping the quiescent current further. Operating temperature spans -40°C to 125°C, covering both cold-start industrial enclosures and hot engine-bay environments.
TO-220-5 Full Pack — thermal and mounting
Housed in a TO-220-5 Full Pack (TO-220FP-5), the through-hole package has a fully moulded back — no exposed metal tab — so it can be bolted directly to a heatsink or chassis without an insulating pad. The five-pin layout provides dedicated input, output, ground, enable, and a no-connect pin; verify the pinout against the datasheet before laying out the PCB. At 2A output, the power dissipation (V_in - 12V) × 2A will require a heatsink for input voltages above about 14V. The Full Pack's junction-to-case thermal resistance is higher than a standard TO-220 with an exposed tab, so the heatsink selection must account for that.