KF33BD-TR

KF33BD-TR is a 3.3 V fixed-output low-dropout regulator from STMicroelectronics in SO-8, supplied on tape and reel — the -TR suffix is the reel form of the KF33BD code in the ST ordering table, while KF33BDT-TR is the separate DPAK version and must not be cross-quoted. It delivers up to 500 mA with ±2% output accuracy at 25 °C, accepts inputs up to 20 V and stays stable with only a 2.2 µF output capacitor. Dropout is 0.4 V typical and 0.7 V maximum at 500 mA, supply-voltage rejection is 70 dB typical, and quiescent current is 50 µA typical with the inhibit input off and 500 µA on, so the TTL-compatible inhibit pin doubles as a clean logic shutdown for sequenced 3.3 V rails. Selection advice: quote this code when a legacy rail needs an inhibit function in SO-8, and check dropout headroom at your worst-case input voltage before committing. ST lists the part as Active. Parameters verified against STMicroelectronics documentation.