The ADP165/ADP166 are very low quiescent current， low dropout （LDO）， linear regulatorsthat operate from 2.2 V to 5.5 V and provide up to 150 mA of output current. The low 120 mV dropout voltage at a 150 mA load improves efficiency and allows operation over a wide input voltage range. The ADP165/ADP166 are specifically designed for stable operation with a tiny 1 μF ± 30% ceramic input and output capacitors to meet the requirements of high performance， space constrained applications. The ADP165/ADP166 are available in seven fixed output voltage options， ranging from 1.2 V to 3.3 V， and an adjustable output option. The ADP165 also includes a switched resistor to discharge the output automatically when the LDO is disabled. The ADP166 is identical to the ADP165， but it does not include the output discharge function. Short-circuit and thermal overload protection circuits prevent damage in adverse conditions. The ADP165/ADP166 are available in a tiny 5-lead TSOT， a 6-lead LFCSP， and a 4-ball， 0.5 mm pitch WLCSP package for the smallest footprint solution to meet a variety of portable power applications.