3-Channel Ultra High Efficiency Quad-Mode™ LED Driver

The CAT3643 is a high efficiency Quad-Mode™ fractional charge pump that can drive up to three LEDs programmable by a one wire digital interface. The inclusion of a 1.33x fractional charge pump mode increases device efficiency by up to 10% over traditional 1.5x charge pumps with no added external capacitors.

Low noise input ripple is achieved by operating at a constant switching frequency which allows the use of small external ceramic capacitors. The multi-fractional charge pump supports a wide range of input voltages from 2.4V to 5.5V.

The EN/DIM logic input functions as a chip enable and a digital dimming interface for current setting of all LEDs. Six different current ratios are available via the interface.

The device is available in the tiny 12-pad XQFN 2.5 x 2.5mm with max height of 0.4mm or in 16-pad TQFN or 12-pad TDFN 3mm x 3mm package with a max height of 0.8mm.

Catalyst Semiconductor's Quad-Mode™ 1.33x charge pump switching architecture is patented.