LED electronic TFT Display Module brightness control conversion technology

LED electronic display is composed of many independent pixels (light emitting element) arranged in due to pixel separation, determine its emission control and drive only in digital form. The light emitting state of these pixels are simultaneously controlled by the controller, independent drive. True color video display means on the brightness of each pixel is controlled separately, and to the required scan time synchronization to complete. Large screens are composed of tens of thousands of pixels, which makes the system more complex than the two values ​​are greatly increased in terms of large-screen displays, and overall a higher data transmission speed requirements. Each pixel is set to a conventional D / A is clearly unrealistic, must find a can minimize system complexity and the performance as high as possible solutions. lcd 128x64
By the vision theory know that people are feeling the average brightness of pixels can be determined by its on / off duty cycle. That is, as long as the pixel is lit on / off duty cycle adjustment, the luminance control can be achieved. For LED electronic display, this means that as long as the representative of pixel brightness light-emitting pixel digital conversion is time (D / T conversion), namely to achieve a brightness of D / A conversion.
That this pixel on / off duty cycle. Since the function f (i) in terms of all the pixels can be in common, and thus the above formula shows that, as long as f (i) of each pixel centralized control, can achieve full-screen independent of each other but all the pixels simultaneously to the D / T conversion.
Large-screen display driver circuit is usually a "serial shift + latch + driver" structure, in order to minimize data transfer cable. To full screen while achieving the above formula, as long as all unified by the ST signal f (i) control can be. Of course, doing so on the premise that requires the shift register is stored in the control data of each pixel in the same positions of power, and this can be done by pre-processing the data. 320x240 lcd display