ASTLC5507 - CONFIGURABLE ALL-IN-ONE CHIP FOR SMALL TFT-LCD SCREENS

The ASTLC5507A is a single chip solution dedicated to small size color TFT-LCDs (typically digital still cameras). It combines on the same substrate a source driver, a gate driver, a timing controller and a power supply circuit. The system can be configured either through a 3-wire serial interface or through several individual control pins.

The 640-output channels source driver has 6-bit resolution or 8-bit if the dithering technique function is selected. The gamma correction is implemented with a resistor ladder using 6 sections of reference voltages. These can reference voltages can be supplied from the outside or generated (and adjusted) on-chip.

A DC-to-DC controller and several charge pumps form the on chip power management circuit. The DC-DC generates the panel backlight supply voltage while charge pumps are used to generate the gate driver supply and common drivers supply voltages. The DC voltage level of the output common signal can be adjusted through a variable external resistor and the peak-to-peak amplitude can be selected through the setting of 3 external pins.

The timing controller supports 8 different timings suitable for small size color TFT panels with PAL and NTSC.

• System-on-chip (SOC) for small size color TFT-LCDs, including:
  - Source driver with selectable 640, 558, 528 and 480-channels, 6-bit (64 grayscale) resolution, line inversion, gamma correction with adjustable references
  - Gate driver: 242-outputs
  - Timing controller supporting 8 different timings
  - CCIR 656 interface compatible with ITU-R BT.656 recommendation
  - Contrast, brightness, hue and saturation color adjustment
  - DC-DC controller of back-light power supply
  - Charge pump for gate driver output: +12.5V/-12.5V
  - 3-wire serial interface for system configuration
  - Stand-by mode
• LCD driver supply voltage: 3.0V ~ 3.6V
• Charge Pump supply voltage: TBD ~ 3.6V
• Digital supply voltage: 2.7 ~ 3.6V
• Operating frequency: 27MHz
• COG package