Fixed 3.3 V rail for medium-current loads
The Texas Instruments LP2950CDT-3.3/NOPB is a positive fixed-output LDO regulator delivering 3.3 V at up to 100 mA. It is built for applications where a clean, regulated 3.3 V rail is needed from an unregulated or higher-voltage supply — think microcontroller power, sensor bias, or auxiliary rails in industrial and automotive systems. The input can go as high as 30 V, which gives you headroom for 12 V or 24 V buses, battery stacks, or lightly regulated intermediate rails without needing a pre-regulator.
Maximum dropout voltage is 0.6 V at 100 mA load. That means the input must stay at least 0.6 V above 3.3 V (so 3.9 V minimum) to maintain regulation at full current. If your rail sags below that, the output follows it down — a common failure signature when the upstream supply is marginal. Quiescent current is 120 µA typical. For always-on circuits or battery-backed rails, that 120 µA is the standing draw before any load current — low enough to keep a coin cell from draining overnight, but not as aggressive as the ultra-low-Iq LDOs aimed at energy-harvesting designs.
Protection and temperature range
Built-in over-current and over-temperature protection mean the part folds back or shuts down before it lets the magic smoke out. On a repair bench, that often saves the regulator itself — the scorch mark ends up on the load side, not the LDO.
Housed in a TO-252-3 (DPak) surface-mount package with a metal tab on the drain/output pin. In a 100 mA application the dissipation is low (under 0.3 W at 3 V drop), so a modest pad is usually enough.