Analog Devices ADP166 series features low quiescent current, low dropout (LDO), linear regulators that operate from 2.2V to 5.5V. ADP166's low 120mV dropout voltage at 150mA load improves efficiency and enables operation over a wide input voltage range. The regulator's short-circuit and thermal overload protection circuits prevent damage in adverse situations. Designed for stable operation with a tiny 1µF ±30% ceramic input and output capacitors, the devices meet the requirements of high performance, space-constrained applications. The ADP166 regulators are well-suited for a range of portable power applications including portable & battery-powered equipment, post-DC-to-DC regulation, portable medical devices, and wireless sensor network (WSN) devices.