Meeting report Zhoutianyu 2015-1-10
1. the delay of DAC and buffer 2. gamma with linear DAC 3. two-stage R-DAC
1. the delay of DAC and buffer
2. gamma with linear DAC Usually, gamma correction is realized by using non-linear DAC architecture Since the non-linear DAC architecture uses piece wise method to fit the gamma curve, precision problem is a considerable disadvantage in this architecture. Adjustable Gamma Correction Circuit for TFT LCD
the upper left is an ‘Applied voltage to LCD transparency’ curve, while the upper right is the gray level curve that we are going to present, and the lower left is the gamma curve of the input to output transformation. The actual value of γ may range from about 2.2 to 2.6 Adjustable Gamma Correction Circuit for TFT LCD
Adjustable Gamma Correction Circuit for TFT LCD
Adjustable Gamma Correction Circuit for TFT LCD
Simulation Result Adjustable Gamma Correction Circuit for TFT LCD
Advantage of this method Simplify the efforts of the resistor issue A better match of gamma curve 3) Less external reference voltage source required 4) Flexibility to support multiple gamme values
3.two-stage R-DAC Adjustable Gamma Correction Circuit for TFT LCD
Adjustable Gamma Correction Circuit for TFT LCD
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