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| Catalyst Semiconductor Adds CAT3626 to Its LED Drivers Catalyst Semiconductor, Inc. expands its family of LED drivers with the CAT3626; a low noise fractional charge pump with an I2C serial bus interface for precise control and programming of up to six white/color LEDs. The CAT3626 is designed to easily and efficiently power backlighting for multiple displays, drive RGB "fashion-lighting" and control flash functions in high-performance portable applications, including cell phones, handheld devices and digital cameras. The CAT3626 is designed with a current regulation scheme which minimizes LED flicker during periods of sudden battery fluctuations - a common problem in portable systems experiencing repetitive load bursts, such as RF or audio power amplifiers. Catalyst helps designers simplify system programming by configuring the CAT3626 LED driver's six output channels into three separate banks, with each bank containing a pair of tightly regulated and matched output channels. This makes the new device ideal for portable products with any combination of multiple RGB LEDs, LCD/keypad backlighting and flash functions. Additionally, an I2C interface allows LED currents within each dual output channel bank to be conveniently and accurately controlled in 0.5mA steps from zero to 32mA, yielding a total device output current of up to 192mA. Targeted at battery-powered portable applications with supply voltages from 2.5V to 5.5V, the CAT3626 maximizes battery life with an automatic 1x/1.5x charge pump, which delivers up to 91% power efficiency. A dedicated Enable control allows the device to be placed into "Zero" current shutdown mode, eliminating battery drain when not in use. In addition to enhanced illumination integrity, the CAT3626 offers low noise input ripple, as well as protection against short-circuit and thermal overload fault conditions. A low profile, 0.8mm, RoHS compliant 4x4mm TQFN package, low external parts count and fixed high frequency (1MHz) operation all contribute to the reduction of system board area. Product Features: - Drives up to 6 LEDs at 32mA each - Three Independent programming zones (pairs of LEDs) - I2C (400kHz) User Interface for Programming and Dimming - Power Efficiency up to 91% - Accurate 0.5mA Dimming Resolution - Automatic 1x/1.5x Fractional Charge Pump - Very Low Noise Input Ripple - Fixed High Frequency Operation (1MHz) - "Zero" Current Shutdown Mode - Soft Start and Current Limiting - Thermal Shutdown Protection - 16-lead TQFN 4mm x 4mm Package - 100% RoHS-compliant Green Package. write your comments about the article :: © 2006 Computing News :: home page |