5 V fixed output, 100 mA — sizing the rail
The LP2950CZ-5.0/LFT8 is a single-output positive LDO from Texas Instruments, delivering a fixed 5 V at up to 100 mA. The 0.6 V maximum dropout at full load means the input rail must stay above 5.6 V to maintain regulation — a 5 V rail from a 6 V battery or a 7.5 V intermediate bus works; a 5.2 V rail does not.
Dropout and quiescent current — the headroom trade
Quiescent current is 120 µA typical, rising to 14 mA max under heavy load or over-temperature. That Iq floor is low enough for always-on rails in industrial sensors or microcontrollers, but the 14 mA ceiling means the thermal budget at 100 mA output includes the dropout power plus the supply current — roughly 0.6 V × 100 mA + 30 V × 14 mA = 480 mW worst-case, which the TO-92-3 package can handle with adequate copper on the leads.
For new designs, a pin-compatible replacement should be evaluated — the LP2950 family includes active TO-92-3 variants with the same 5 V fixed output and 100 mA rating.
Through-hole TO-92-3 — board integration
The TO-92-3 (TO-226AA) through-hole package is a 3-lead inline plastic case, 0.100-inch pitch. It is intended for PCB mounting with the leads soldered or socketed.