200 mA LDO with 80 dB PSRR across the audio band
The STMicroelectronics LD39020ATPU33R is a fixed 3.3 V output linear regulator delivering 200 mA from a 4-XDFN exposed pad package. It is designed for noise-sensitive supply rails where the 80 dB PSRR at 1 kHz (dropping to 55 dB at 100 kHz) filters upstream switching ripple before it reaches the load. A 0.35 V maximum dropout at the full 200 mA load means the input rail needs only 3.65 V to maintain regulation — useful in battery-powered designs where the cell voltage sags under load.
Quiescent current and thermal envelope
Quiescent current is 40 µA typical, keeping the regulator's own draw low in always-on domains like RTC supplies or sensor bias rails.
Protection and compliance
On-chip protection includes over-current, over-temperature, and soft-start — the soft-start limits inrush current into the output capacitor during power-up, preventing the input rail from dipping. The part is active in production and ROHS3 compliant.