CAT3637

www.DataSheet4U.com CAT3637 6-Channel Programmable High Efficiency Quad-Mode™ LED Driver FEATURES „ „ „ „ „ „ „ „ „ „ „ High efficiency 1.33x charge pump Quad-Mode charge pump: 1x, 1.33x, 1.5x, 2x Drives 6 LEDs between 30mA and 0mA each 1-wire EZDimTM interface with 2mA step 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 Tiny 3mm x 3mm, 16-pad TQFN package DESCRIPTION The CAT3637 is a high efficiency Quad-Mode fractional charge pump that can drive up to six LEDs programmable by a 1-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 2.5V to 5.5V. The EN/SET logic input functions as a chip enable and a digital programming interface for setting the current in the LED channels. The 1-wire pulse-programming interface supports 15 linear steps from zero current to 30mA fullbrightness in 2mA steps. The device is available in a tiny 16-pad TQFN 3 x 3mm package with a maximum height of 0.8mm. Catalyst Semiconductor’s Quad-Mode 1.33x, charge pump switching architecture is patented. Package Marking JAAM APPL...