2-W LED Driver Handles High-Power Backlighting Applications
The CAT4240 boost converter from Catalyst Semiconductor Inc. delivers up to 750-mA switch current and high voltage—up to 38 V. The result is a device well-suited for a wide array of backlighting applications, ranging from 1-W LEDs in series to multiple strings of lower-power LEDs.
The CAT4240 provides a 2-W output from a 3- to 5-V supply and up to 6 W when configured with a higher-voltage, split supply of 9 to 12 V. Additionally, its low-noise, high-frequency switching scheme and fully integrated features eliminate the need for external components associated with soft-start and overvoltage protection, reducing noise and saving board space.
The soft-start feature eliminates excessive "in-rush" currents that can occur during initial power-up. In the event of an open-LED fault condition, an internal overvoltage protection circuit will place the device into a low-power operating mode, restricting the output voltage to safe levels without the need for external circuitry. Integrating this and the fixed-frequency 1-MHz switching architecture eliminates the need for external components and the associated cost and board space overhead.
The CAT4240 LED driver costs $0.84 each in quantities of 10,000. Samples are available now. Projected lead time for production quantities is six to eight weeks.
For more information, check out www.catsemi.com.