Sep 10 2008
ON Semiconductor, a global leader in high performance, energy efficient, silicon solutions, has introduced the NCP5890 - a unique lighting management device that integrates LCD backlighting, fun light controls and ambient light sensing into a tiny 3 mm x 3 mm x 0.5 mm package.
With its 30-volt (V) output capability, the device drives LEDs in series to achieve homogeneous backlight over the LCD screen. In addition, the NCP5890 controls three sets of white LEDs or RGB LEDs to create fun light patterns on keypads or chassis in a unique combination with backlighting. The driver also extends battery life by adjusting the backlight current according to the ambient light level. The NCP5890 is a dedicated solution for compact smart phone and portable media player applications.
“Larger LCD screens and LED lighting effects are popular features in today’s portable electronics,” said Manor Narayanan, vice president and general manager of ON Semiconductor’s Digital and Consumer Products Group. “To meet all these illumination requirements, hardware designers commonly need to utilize several LED drivers. With restricted board space, achieving these more sophisticated lighting effects has often required extensive software programming and microcontroller resources. ON Semiconductor now provides a simpler, single chip, silicon solution with multiple command-based light effects that enable hardware engineers to meet their specific lighting and power design targets.”
Featuring high overall power efficiency of up to 90 percent at 1.3 megahertz (MHz) oscillator frequency, the NCP5890 inductive boost LED driver delivers up to 30 V at output. It can drive up to eight LEDs in series for LCD backlight and fun lighting. The device supports ambient light sensing, a feature required in smart phones to reduce power consumption and increase user comfort. The NCP5890 also features built-in gradual dimming that creates fade-in and fade-out effects. Both ambient light sensing and gradual dimming are automated built-in functions that can be activated with simple I²C commands. The device supports the I²C protocol with two separate address options. The integrated driver also extends battery power with a true cut-off function that limits the leakage output current in shut-down mode.