Editor's note: ON Semiconductor has introduced three new white LED drivers designed for backlighting applications in mobile phones, digital cameras, MP3 players and other portable consumer electronics devices to drive high-brightness LEDs. With up to 90% energy efficiency, these three new devices are available in an ultra-thin 0.6 mm package that helps designers meet the stringent power and board space requirements of today's battery-powered portable electronic devices. Marie Capron, director of low-voltage products business at ON Semiconductor, said: "LED drivers in portable application displays typically use inductive solutions or charge pump solutions, but our customers have a very clear preference. Inductive solutions are typically step-up. The architecture of the series LEDs, the charge pump solution is parallel LEDs, thus eliminating the need for inductors. To meet the needs and preferences of all portable product customers, we have expanded the LED driver product line, providing both solutions and providing important circuit protection. Value-added features also save valuable board space.†Inductor Solutions The NCP5010 provides up to 22 volts (V) and is typically powered by 2 to 5 series white LEDs for LCD backlight applications. The NCP5010 has an energy efficiency of up to 84%, a shutdown current of 1 microamperes (μA), and an operating input voltage range of 2.7 V to 5.5 V. It features true cut-off, short circuit and overvoltage protection, and provides undervoltage cutoff. This space-saving device is packaged in a flip-chip package and occupies less than 3 mm2 of board area and 0.6 mm height. Its small size makes it the ideal glare for the thinnest portable products. Its integrated pulse width modulation (PWM) boost converter has a frequency of 1 megahertz (MHz) and is integrated with a Schottky rectifier that can be used with small inductors and Capacitor optimized board design saves more board space. The charge pump solutions NCP5604A and NCP5604B drive three or four LEDs, each with a current of 25 milliamps (mA). The current matching tolerance is only 0.5%, ensuring good LED brightness and good performance. They are up to 90% efficient, have a quiescent current of less than 1 μA, operate from an input voltage range of 2.7 V to 5.5 V, and feature unique short-circuit and overvoltage protection. Both the NCP5604A and NCP5604B are available in a slim QFN package (WQFN) that occupies only 0.8 mm of space, making them ideal for space-constrained ultra-thin phones. Package and Price The NCP5010 is available in a lead-free, 8-pin, 1.7 mm x 1.7 mm x 0.6 mm flip-chip package. The unit price for each 3,000 piece is $0.67. The NCP5604A is available in a lead-free WQFN-16 package and is priced at $0.69 per unit in 3,000-piece quantities. The NCP5604B is available in a lead-free WQFN-16 package and is priced at $0.66 per unit in 3,000-unit quantities. For more technical information, please visit
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