ASTLC5502 - ALL-IN-ONE CHIP FOR SMALL-SIZE TFT-LCDs
GENERAL DESCRIPTION
The ASTLC5502A is a single chip solution dedicated to small size color TFT-LCDs. 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 288-output channels source driver is a 64-grayscale levels driver enabling a 262K-color resolution. The gamma correction is implemented with a resistor ladder using 4 sections of reference voltages.
The 240-output channels gate driver can be used in single or dual scan modes by level shifting single or dual logic input pulses into high-voltage outputs between VGH and VGoff.
A DC-to-DC controller and a charge pump form the on chip power supply circuit. The DC-DC generates the panel backlight supply voltage while the charge pump is used to generate the gate driver and common electrode supply voltage. 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.
FEATURES
- System-on-chip (SOC) for small size color TFT-LCDs, including:
- Source driver with 288-channels, 6-bit resolution, line inversion and gamma correction with 5 external references
- Gate driver: 240-outputs
- Timing controller supporting 8 different timings
- DC-DC controller of back-light power supply
- Charge pump for gate driver output: +12.5V/-12.5V
- 3-bit programmable DC voltage level for VCOM
- 3-wire serial interface for system configuration
- Stand-by mode - LCD driver supply voltage: 3.0V ~ 5.5V
- Digital supply voltage: 2.7 ~ 3.6V
- Operating frequency: 27MHz
- COG package
Block diagram
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