Linear Technology‘s LTC3388 is a low quiescent current synchronous buck converter than can deliver up to 50mA of continuous output current from a 2.7V to 20V input supply. Its no-load operating current of only 720nA makes it suitable for a wide range of applications including “keep-alive,” energy harvesting and industrial control power. The LTC3388 utilizes hysteretic synchronous rectification and can offer over 90% efficiency for loads ranging from 15uA to 50mA.
The part incorporates an undervoltage lock-out feature to disable the converter when the input voltage drops below 2.3V, reducing quiescent current to only 400nA. Once in regulation (at no load), the LTC3388 enters a sleep mode to minimize quiescent current to only 720nA. The buck converter then turns on and off as needed to maintain output regulation.
The LTC3388 is offered in two different versions, each with different pin-selectable output voltages. The LTC3388-1 offers 1.2V, 1.5V, 1.8V or 2.5V outputs whereas the LTC3388-3 offers 2.8V, 3.0V, 3.3V or 5V outputs.The combination of a 3mm x 3mm DFN package (or MSOP-10) and only five external components offers a compact solution footprint. Pricing starts at $2.95 each for 1,000-piece quantities.