Nanopower Buck-Boost DC/DC with Integrated Coulomb Counter

The LTC3335 is a high efficiency, low quiescent current (680nA) buck-boost DC/DC converter with an integrated precision coulomb counter which monitors accumulated battery discharge in long life battery powered applications. The buck-boost can operate down to 1.8V on its input and provides eight pin-selectable output voltages with up to 50mA of output current.

The coulomb counter stores the accumulated battery discharge in an internal register accessible via an I2C interface. The LTC3335 features a programmable discharge alarm threshold. When the threshold is reached, an interrupt is generated at the IRQ pin.

To accommodate a wide range of battery types and sizes, the peak input current can be selected from as low as 5mA to as high as 250mA and the full-scale coulomb counter has a programmable range of 32,768:1.

The LTC3335 is available in a 3mm × 4mm QFN-20 package.

Applications

* Long Lifetime Primary Cell Battery Applications

* Wireless Sensors

* Remote Monitors

* Dust Networks® SmartMesh® Applications

* 680nA Input Quiescent Current (Output in Regulation at No Load)* 1.8V to 5.5V Input Operating Range* Selectable Output Voltages of 1.8V, 2.5V, 2.8V, 3V, 3.3V, 3.6V, 4.5V, 5V* Integrated Coulomb Counter Measures Accumulated Battery Discharge* ±5% Battery Discharge Measurement Accuracy* Programmable Peak Input Current of 5mA, 10mA, 15mA, 25mA, 50mA, 100mA, 150mA, 250mA* Up to 50mA of Output Current* Up to 90% Efficiency* Programmable Coulomb Counter Prescaler for Wide Range of Battery Sizes* Programmable Discharge Alarm Threshold* I2C Interface* Low Profile (0.75mm) 20-Lead (3mm × 4mm) QFN Package