4 V fixed output, 200 mA — what the dropout tells you
The Toshiba TAR5S40(TE85L,F) is a single-output positive fixed linear regulator delivering 4 V at up to 200 mA. Its maximum dropout voltage is 0.2 V at 50 mA load.
SC-74A / SOT-753 — rework-friendly footprint
The TAR5S40 comes in a 5-pin SC-74A package, also designated SOT-753, with the SMV supplier device package marking. It is a surface-mount part with a small body — about 2.9 mm by 1.6 mm — and the pins are on a 0.95 mm pitch.
Protection and control — ON/OFF pin, over-current, over-temperature
An ON/OFF control pin lets you sequence the rail or shut down the regulator for power saving. The quiescent supply current is 850 µA maximum — not an ultra-low-Iq part, but reasonable for always-on industrial logic where the load current dominates. Over-current and over-temperature protection are built in; the part folds back current on a hard short and thermal-shuts down if the die exceeds the safe junction limit. No reverse-current protection, so keep the output voltage from exceeding the input during power-down.
The TAR5S40 carries an active product status. ROHS3 compliant.