CAT3648

www.DataSheet4U.com CAT3648 4-Channel Ultra High Efficiency Quad-Mode™ LED Driver with 32 Dimming Levels FEATURES „ „ „ „ „ „ „ „ „ „ „ High efficiency 1.33x charge pump Quad-mode charge pump: 1x, 1.33x, 1.5x, 2x Drives up to 4 LEDs at 25mA each 1-wire EZDim™ 32 linear steps Power efficiency up to 92% Low noise input ripple in all modes “Zero” current shutdown mode Soft start and current limiting Short circuit protection Thermal shutdown protection 3mm x 3mm, 16-pad TQFN package DESCRIPTION The CAT3648 is a high efficiency quad-mode fractional charge pump that can drive up to four 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 tradi– tional 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 2.5V to 5.5V. The EN/DIM logic input functions as a chip enable and a digital dimming interface for setting the current in all LED channels. The 1-wire pulse-dimming interface supports 32 linear steps from full-scale down to zero current. The device is available in the tiny 16-pad TQFN 3mm x 3mm package with a max height of 0.8mm. Catalyst Semiconductor’s Quad-Mode™ 1.33x, charge pump switching architecture is patented. Marking JAAN APPLICATION „ „ „ „ LCD Display Bac...