HX8347 - Adafruit

HX8347-G(T)240RGB x 320 dot, 262K color, TFT Mobile Single Chip Driver5.14 Content Adaptive Brightness Control (CABC) functionDATA SHEET Preliminary V01The HX8347-G has support Content Adaptive Brightness Control (CABC) Functionand will output one PWM signal to external LED Driver IC. The PWM signal isautomatics adjust output duty by display image for saving LED backlight powerconsumption.Example: Image A: -20% brightness reduction Image B: -30% brightness reduction Image C: -10% brightness reductionImage A:Brightnessreductionratio -20%Image B:Brightnessreductionratio -30%Image C:Brightnessreductionratio -10%100%90%80%70%50%TransitiontimeTransitiontimeTransitiontime0%TimeFigure 5.41: Example of CABC functionThe general block diagram of the CABC and the brightness control is illustratedbelow:VSYNC, HSYNC, ENABLE,DCLK ( in RGB I/F)Display ControlSignal GeneratorImage DataDisplay DataGeneratorDisplay DataContents AnalysisC[1:0]='00': OffC[1:0]='01','10','11': OnGainDBV[7:0]( BL = `0`)CABC BlockCABC Gain/ DutyDutyPWM_CLK(foscD)PWM ClockDeviderBrightness ControlBlockCABC_PWM_OUT( BL = `1`)BCTRL='0': OffBCTRL='1': OnFigure 5.42: CABC block diagramHimax ConfidentialFor Go-tek OnlyThis information contained herein is the exclusive property of Himax and shall not be distributed, reproduced, or disclosedin whole or in part without prior written permission of Himax.-P.113-October, 2009