Active 15 V fixed-output LDO for 100 mA rails
The STMicroelectronics L78L15CD-TR is a single-output, fixed 15 V positive linear regulator delivering up to 100 mA continuous current. This is an active-production part with ROHS3 compliance, suitable for new designs or BOM refill on existing boards.
The L78L15CD-TR provides 39 dB of power-supply rejection at 120 Hz. This is the attenuation of ripple from a full-wave rectified mains supply — a 1 V peak-to-peak 120 Hz ripple on the input becomes roughly 11 mV on the output. For analog circuits powered from a lightly filtered DC bus, this level of rejection keeps hum out of the signal chain. Quiescent current is 5.5 mA typical and maximum supply current is 6 mA. The 100 mA output covers local regulation for small analog loads — op-amp rails, sensor supplies, or reference buffers — without the thermal overhead of a larger regulator. Protection features include over-current, over-temperature, and short-circuit shutdown. The operating temperature range is 0°C to 125°C, which covers commercial and most industrial ambient conditions, though not extended cold environments.
The 8-SOIC footprint is a standard surface-mount package with 1.27 mm pin pitch. The tape-and-reel option supports automated pick-and-place assembly. No exposed thermal pad — power dissipation is through the package leads and copper area on the PCB.