The LTC3553 is a micropower, multifunction power-management IC (PMIC) for portable Li-Ion/Polymer battery-based applications. The LTC3553 integrates a USB-compatible linear PowerPath manager, a stand-alone battery charger, a high-efficiency synchronous buck regulator, a low-dropout linear regulator and pushbutton controller in an ultrathin (0.55-mm) 3-mm x 3-mm QFN package. A pin-selectable standby mode reduces battery drain current to just 12 µA while keeping all outputs in regulation, extending battery run time. The LTC3553 is well suited for low power portable device applications, including personal navigation devices (PNDs), media players and handheld medical and industrial devices. The LTC3553’s PowerPath manager, with automatic load prioritization, seamlessly manages the transition between multiple input sources to power the load, while delivering up to 400 mA of battery charge current from a USB port or a 5-V wall adapter input. The device’s integrated synchronous buck regulator delivers up to 200 mA of output current with a regulated output voltage that is adjustable down to 0.8 V. The low-dropout (LDO) regulator provides up to 150 mA of output current. The LTC3553 is available from stock in a compact, ultra low-profile (0.55-mm) 3-mm x 3-mm UTQFN-20 package. Pricing starts at $2.25 each for lots of 1000. LINEAR TECHNOLOGY CORP., Milpitas, CA. (408) 432-1900.