NATIONAL Semiconductor, represented by Arrow Electronics , has introduced a chipset that combines low power and advanced interface design for better colour, contrast and battery life.
This new solution offers features that enable customers to differentiate products easily and cost effectively and supports all standard industry requirements.
Available for sampling late next month, this chipset will enable lighter and thinner cell phones that have longer battery life and versatile video features such as an adjustable display quality switch to save energy.
The new chipset is comprised of two integrated circuits, the FPD94128 controller/column driver and the FPD93140 power supply/gate driver.
Together they form a complete solution for driving amorphous silicon active matrix LCD (AMLCD) panels used in mobile phones that support full color graphics, video and still images.
The chipset features an image dependant backlight controller for the reduction of backlight intensity, which translates to longer phone usage time between charges.
Typical backlight power of 150mW swamps the power used by the display. Detection of high contrast images can automatically cut the display lighting power by a programmable amount, potentially reducing the lighting power by 50 per cent or more.
External ambient light sensors can also reduce display lighting power and enhance appearance through programmable brightness controls within the chip.
The FPD94128 features programmable colour depth that allows selection of 3-bit, 9-bit, 12-bit or 18-bit color modes, which allows users to trade-off power consumption for display quality.
For example, when users are running low on battery power or want to extend usage time, they can switch then from phone display from the full 18-bit (262K colour) mode to 12-bit (4K colour) or 9-bit (512 colour) mode. This reduces chip power consumption by 40 percent in the 4K colour mode.
Additionally, the chipset has a versatile video interface, accepting data in 18-bit RGB or 8-bit or 16-bit 4:2:2 Y'CbCr.
This allows direct connection to image sensors in camera-enabled phones using a more efficient 8-bit interface when sub-sampled Y'CbCr data is available from the sensor.
For mobile phones capable of receiving video images, the built-in Y'CbCr -RGB converter allows direct connection to the phone's MPEG decoder.