The LTC3129 is a synchronous buck-boost converter that delivers up to 200mA of continuous output current from a wide variety of input sources including single or multiple-cell batteries as well as solar panels and supercaps. Its 2.42V to 15V input range and 1.4V to 15.75V output range provide a regulated output with inputs above, below or equal to the output. The low noise buck-boost topology provides a continuous transition through all of the operating modes, making it ideal for applications that must maintain a constant output voltage, even as the input source voltage transitions through the output voltage. It also includes programmable maximum power point control (MPPC) capability, ensuring maximum power extraction from non-ideal power sources such as photovoltaic cells.Quiescent current of only 1.3µA makes the LTC3129 well suited for always on and energy harvesting applications in which extended battery run time is of primary importance. The constant 1MHz switching frequency ensures low noise and high efficiency, while minimizing the size of the external components. The combination of tiny externals and a 3mm x 3mm QFN or MSOP-16E package provides a very small solution footprint. Other features include a power good indicator, current-mode control, internal compensation thermal shutdown and output disconnect.The LTC3129-1 version offers eight fixed output voltages from 2.5V to 15V that are user-programmable and eliminate the resistor divider required on the adjustable version.Both the LTC3129EUD and LTC3129EUD-1 are available in a 16-lead 3mm x 3mm QFN package. The LTC3129EMSE and LTC3129EMSE-1 are offered in a thermally enhanced 16-lead MSOP package. Pricing starts at $2.95 each for 1,000-piece quantities. Industrial grade versions are guaranteed to operate over a -40°C to 125°C operating temp range and are priced at $3.25 each.
