The LTC3675/LTC3675-1 are a digitally programmable high efficiency multioutput power supplies plus dual string LED driver ICs optimized for high power single cell Li-Ion/Polymer applications. The DC/DCs consist of four synchronous buck converters (1A/1A/500mA/500mA), one synchronous boost DC/DC (1A), and one buck-boost DC/DC (1A) all powered from a 2.7V to 5.5V input. The 40V LED driver can regulate up to 25mA of current through two LED strings with up to 10 LEDs each. The LED driver may also be configured as a general purpose high voltage boost converter.

DC/DC enables, output voltages, switch slew rates and operating modes may all be independently programmed over I²C or used in standalone mode via simple I/O and power-up defaults. The buck DC/DCs may be used independently or paralleled to achieve higher output currents with a shared inductor. LED enable, 60dB brightness control and up/down gradation are programmed using I²C. Alarm levels for low V_IN and high die temperature may also be programmed via I²C with a maskable interrupt output to monitor DC/DC and system faults.

Pushbutton ON/OFF/RESET control and a power-on reset output provide flexible and reliable power-up sequencing. The LTC3675/LTC3675-1 are available in a low profile (0.75mm), thermally enhanced 44-lead 4mm × 7mm QFN package.

Applications

• High Power (5W to 10W) Single Cell Li-Ion/Polymer Applications
• Portable Industrial Applications, Handy Terminals, Portable Instruments
• Multioutput Low Voltage Power Supplies

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.