LED Backlight Driver Reduces Current Requirements Up To 50 Percent For Small Format Displays

This flexible architecture simplifies the system designer’s objective to optimize power management in a broad range of low-power, low-voltage products that require backlighting for small-format displays and/or keypads found in consumer, medical, industrial and instrumentation electronics devices.

For challenging applications such as maritime and portable navigation devices, radar scanners and consumer handsets, which require consistent display viewing in a variety of ambient lighting environments, the ADP8860 supports 1.7 to 3.3 V I/O operation. The device’s configurable architecture improves ease-of-use by automatically detecting ambient light levels and adjusting backlighting brightness according to changing light conditions. Like ADI’s other LMS devices, the ADP8860’s LMS capability enables the device to automatically determine and adjust for the minimum gain required as light level changes and reduces power consumption up to 50 percent when compared with traditional charge pump devices that use the same lighting gain for all conditions. Multi-zone lighting capability is also available to support the main display, as well as other displays including navigation, special functions, keypad, and indicator displays where significant power savings can be realized while maintaining the required viewing light levels. The LMS also helps to minimize the processor’s involvement, extending device autonomy – the time required between charges – and increasing the battery days-of-use time by up to 35 percent.

Featuring a parallel configuration, the single-chip ADP8860 can control up to seven LEDs – six at 30 milliamps (mA) maximum and one at 60 mA – offering sophisticated dimming and fade-in/fade-out capabilities. This flexibility delivers independent LED control to achieve minimum/maximum current and fade-in/fade-out times, or in grouped LED control to offload the processor from fade-in/fade-out duties and conserve power. For example, designers can configure a small group of LEDs to backlight the display, and assign individual LEDs to drive keypad lighting, and network connectivity and charge indicator lights. The single-chip ADP8860 backlight driver also enables system designers to quickly and easily upgrade non-LMS devices to provide the desired sophisticated fading and dimming functions, as well as extended battery life, to offer users an enhanced media viewing experience in a variety of lighting conditions.