E-mail for more information Company's other products E-mail to a colleague See similar products Printer friendly format

Semtech Corp. announces the SC4505, an integrated boost (step-up) DC/DC converter for driving white LEDs in LCD backlight and camera-flash applications in cell phones and PDAs. The SC4505 features a 2 A power switch with an adjustable output voltage of up to 28 V to drive two strings of up to six LEDs per string using a single inductor. Each string features an independent user-selectable current source with the backlight string supporting up to 75 mA and the flash string supporting up to 125 mA. The high power level can accommodate high-current LEDs for brighter displays. The device supports independent control of the backlight and flash functions through separate pins. Backlight dimming can be achieved through digital PWM control signals with a range of 50 Hz to 50 kHz, which maintain peak LED current for maximum brightness. The camera-flash string features a user-controllable flash timeout that reduces LED burn out. In addition, the flash can be set to 20% of maximum flash current (torch or spotlight mode) for continuous LED lighting.

Semtech Corp.