CAT3636

www.DataSheet4U.com CAT3636 6-Channel Quad-ModeTM Fractional LED Driver in TQFN3x3 FEATURES „ „ „ „ „ „ „ „ „ „ „ „ „ „ „ „ High efficiency 1.33x charge pump Quad-mode charge pump: 1x, 1.33x, 1.5x, 2x Drives up to 6 LEDs at 32mA each 1-wire EZDimTM LED current programming 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-lead TQFN package LCD Display Backlight Color RGB LEDs Cellular Phones Digital Still Cameras Handheld Devices DESCRIPTION The CAT3636 is a high efficiency quad-mode fractional charge pump that can drive up to six 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 2.5V to 5.5V. The EN/SET logic input functions as a chip enable and a “1-wire” addressable interface for control and current setting of all LEDs. Three groups of two LEDs can be configured with independent LED currents between 0.25mA and 32mA. The device is available in a tiny 16-lead TQFN 3mm x 3mm package with a max height of 0.8mm. The 1.33x charge pump with two fly capacitors...