AMOLED Driver Design Of Digital Part

AMOLED display has the advantages of high brightness,low power consumption,fast response speed,good flexibility and high luminous efficiency.It is considered as one of the main display technologies of the next generation.Along with AMOLED display panel manufacturing technology and display screen resolution has been improved.The performance of the drive chip is directly related to the quality of the display image,so The research on AMOLED drive circuit technology has strong engineering value.In the light of the small and medium size specific arrangement AMOLED display panels,we design a resolution of 1920 RGB 1200 digital driving circuit.Subpixel coloring algorithm based on weight factor and gamma correction algorithm based on intermediate difference algorithm are adopted.Calculation and analysis results show that:to determine the weighting factor of sub pixel shading algorithm for 0.5,can effectively improve the uniformity of the image edge problem,based on the weighting factor of sub pixel shading algorithm can solve the image edge caused by image gray-scale changes greatly the problem of uneven color,and in reducing the source level drive a third number at the same time to reach agreement and the original image to show the effect;The contrast of images can be improved by using the gamma correction algorithm based on the intermediate difference algorithm.AMOLED drive circuits include analog and digital circuits.The digital drive circuit mainly includes 16-bit SPI interface circuit,24-bit RGB interface circuit,sub-pixel shading circuit,gamma correction circuit,gate level driver circuit,and source level drive circuit.The circuit USES the SPI+RGB linterface combination to provide interface data and instruction transmission,wherein the SPI interface controls the reading and writing of data and instructions through the first three signal bits.The RGB interface is responsible for transmitting the pixel data sent by the upper computer.and every three DCLK signals are one output cycle,and each output cycle sends the pixel information of 3 pixels.The subpixel shading circuit and gamma correction circuit are based circuit adopts the shift register of 1200-bit,which produces 1200 rows of gate end line selected communication number,and the rise of each HS signal is shifted to the left.The circuit source level drive circuit adopts the Ram-less technology,and the chip output port USES the 2-level latch structure instead of Ram memory,which can reduce the area of the chip and save the manufacturing cost through the latch circuit.Using the Modelsim software to build the verification platform to complete the function terification of the digital drive circuit,the verification results show that the digital drive circuit designed in this paper completes the booking function and meets the design requirements.