Fixed 1.8V rail for post-regulation
The LP3962EMPX-1.8/NOPB is a fixed-output positive LDO regulator from Texas Instruments, delivering 1.5 A at 1.8 V from a maximum input of 7 V. The fixed output eliminates the external resistor divider, saving two components and one feedback-node noise path on the board.
Protection set and quiescent draw
Built-in over-current, over-temperature, and short-circuit protection mean the regulator survives a sustained output short or a thermal event without external crowbar circuitry. The 9 mA quiescent current is the standing draw when the output is enabled; the Enable pin (active-high logic input) lets a system controller shut down the regulator to near-zero leakage when the 1.8 V rail is not needed.
Temperature grade and package fit
The SOT-223-5 (TO-261-5) surface-mount package has a large centre tab that conducts heat to the board copper; the datasheet's thermal-resistance figure assumes a minimum pad area, so the board layout determines the actual current derating above 85°C ambient.