The AAT1223 is a single-chip solution for TFT LCD panel application. It contains multi-channel TFT LCD power solution that provides a boost PWM regulator, positive charge pump, VCOM operational amplifier, voltage detector, low dropout linear regulator, GPM controller up to 35V for TFT LCD display, and WLED backlight driver.
The LED driver can drive 4 strings of WLEDs using constant current source. The mismatch current of every string is within 3%.
The PWM controller consists of an on-chip voltage reference, oscillator, error amplifier, current sense circuit, comparator, under-voltage lockout protection and soft-start control circuit. The thermal and power fault protection prevents excessive power from damaging the internal circuit.
The positive charge pump generates VGH voltage (gate high voltage) setting by external resistor divider. For the flicker compensation, VGHM will be connected to VGH when VFLK is low and connected to RE when VFLK is high. In addition, AAT1223 contains one operational amplifier capable of supplying 150mA to VCOM.
With minimal external components, the AAT1223 offers a simple and economical solution for TFT LCD and backlight power management.