Linear Technology’s LTC3111 synchronous buck-boost dc-dc converter produces 1.5 A of output current from a wide range of power sources, including single- or multiple-cell batteries, supercapacitor stacks, and wall adapters. The device’s 2.5- to 15-V input and output voltage range delivers a regulated output from inputs above, below, or equal to the regulated output. Thanks to its low-noise buck-boost topology, a jitter-free transition is possible between buck and boost modes, suiting it for noise-sensitive applications. The converter’s default 800-kHz switching frequency can be synchronized to an external 600-kHz-to-1.5-MHz clock. Proprietary third-generation buck-boost pulse-width-modulation (PWM) circuitry reduces noise and boosts efficiency. In fact, along with four internal low RDS(ON) N-channel MOSFETs, the LTC3111 uses a single inductor to push efficiencies up to 95%. User-selectable Burst Mode operation lowers quiescent current to 49 µA to improve light-load efficiency and extend battery run time.