Linear Technology’s LTC3113 is a synchronous buck-boost converter delivering 3A of output current from a nominal 3.3V power source, Li-ion/Polymer battery or up to 1A from dual cell alkaline/NiCad/NiMH batteries. The converter’s 1.8 to 5.5V input range and 1.8 to 5.5V output range provides a regulated output from an input voltage above, below or equal to the output. It is also suited to maximise the energy available from a two super capacitor stack. The proprietary buck-boost topology delivers a continuous transition through all operating modes, making it suitable for applications that must maintain a constant, low noise output voltage even as the input voltage falls below the output, adding up to 25% more battery run time. Its constant switching frequency is user programmable from 300kHz up to 2MHz to maximise the balance between efficiency and external component size.
The combination of tiny externals and a 4x5mm DFN or TSSOP-20E package provides high power density required in high performance applications. The device includes two N-channel MOSFETs and two P-channel MOSFETs (RDS(ON) of 29 and 40mOhm, respectively) to deliver efficiencies of up to 96%. User-selectable Burst Mode operation reduces quiescent current to 40uA, improving light load efficiency and extending battery life. For noise sensitive applications, the Burst Mode can be disabled, offering low noise operation. Other features include soft-start, current limiting, thermal shutdown and output disconnect. It is available in a 16-lead 4x5mm DFN thermally enhanced 20-lead TSSOP package.
