Converter with integrated coulomb counter consumes 680na quiescent current

Linear Technology has announced the LTC3335, a nanopower high efficiency synchronous buck-boost converter with an onboard precision coulomb counter. It is said to deliver up to 50mA of continuous output current with 680nA of quiescent current and programmable peak input currents from 5 to 250mA, the device is suited for a variety of low power battery applications.

Its 1.8 to 5.5V input range and eight user-selectable outputs between 1.8 and 5V can provide a regulated output supply with input voltage above, below or equal to the output. In addition, the device’s integrated coulomb counter provides monitoring of accumulated battery discharge in long-life primary cell applications that have flat battery discharge curves. Typical applications include remote sensors and monitors, and Linear’s Dust Networks SmartMesh wireless sensor network systems.

The LTC3335 is claimed to deliver efficiency of up to 90%. Other features include a programmable discharge alarm threshold and an I²C interface for accessing coulomb count and device programming. The LTC3335is available with an operating temperature range from -40 to 125°C in a thermally enhanced, 20-lead 3 x 4mm QFN package.