Fixed 4.0 V LDO for noise-sensitive analog rails
It targets low-noise analog supply rails where the 63 dB PSRR at 1 kHz cleans up switching-regulator ripple before it reaches an ADC, op-amp, or sensor bias circuit.
Dropout, quiescent current, and temperature range
Maximum dropout is 0.22 V at the full 50 mA load, so the input can sag to 4.22 V and the output still holds regulation — useful on a lightly-loaded 5 V bus or a battery that is nearing end-of-discharge. Quiescent current is 95 µA typical, keeping the always-on power budget low for battery-operated or standby circuits.
Built-in over-current, over-temperature, and short-circuit protection let the regulator survive a momentary output short without external clamp diodes. An Enable pin gives the system designer a way to sequence the rail on/off or shut down the LDO in sleep mode.