| 1. Significance of studyThe peripheral driving system and driving chip is an important and integrant OLED (Organic Emitting Display) technology. It is not only because the test spends much money,material resources,manpower and time, but also the driving system is the key element which can be used to confirm the OLED's quality and performance. A 64×3×80 resolution AMOLED (Active Matrix OLED) has been mentioned in this paper. The display's lead lines include 24 analog voltage data and 6 row and column control signals. Some power signals are also needed.Many driving IC is designed for the PMOLED(Passive Matrix OLED) currently. There is few of driving IC which is designed to drive the AMOLED. The reason is that the AMOLED requires very high voltage data signals and many control signals which are not easy to obtain. The task of the system design is very tough. The design of the application specific driving IC become one synthesis technology that includes electronics,micro-electronics,programmable device,digital signal processing knowledge etc.The target of this paper is using EDA tools to realize the driving system for the 64×3×80 resolution AMOLED. The system can offer the AMOLED the right data and control signals. That's to say, design a driving system which can be used to test and drive the AMOLED, and design an programmable application specific driving IC for the AMOLED which has our own IP(Intellectual Property).2. Universal Project of the driving systemTo realize required functions of this study, the project design is shown in figure1. The FPGA controller gets the display data from the storage memory .The data are processed in the FPGA. After enlarging its bits and DAC processing, the data are sent to the AMOLED pixels. The FPGA controller, which is droved by a global clock, will generate the row and line driving signals. These signals must be transformed by DC-DC chip and analog switch chip, so their wave shape and meet the use of AMOLED. Figure 1 AMOLED driving system project designThe paper's stress is the design of the outer driving system, which include the digital circuit portion and the analog circuit portion.The digital portion include FPGA controller,Display data memory, Configuration device.FPGA controller is the core of the whole design, it offer the OLED display data and control signals referencing the control strategy. At the same time, FPGA can do the data processing work, such as digit-widen etc. The display data are storied in the Display data memory. The configuration data are storied in the configuration device. When powered, FPGA read the configuration data from the configuration device and store it to its SRAM inherent and begin to have the function as designed. The analog portion includes the DAC module and the voltage converter module. The DAC chip translate the digital data output by FPGA into analog voltage data and transfer them to the OLED pixels. And by the effort of DC-DC converter and analog switch, the required control signals which have the right shape and voltage are generated.Take care that: every function subdivision of the FPGA controller is mutually associated, and the design is an organic whole, design must be considered completely. The relationship between digital portion and analog portion should also be noticed.3. The software and hardware realization of the whole system Basic principles that driving system realizes are: strong function, easy to use, high performance, short design period. In fact, all of the system is hardware, but it has used the programmable device FPGA and the FPGA controller's design can be seen as software design.Figure 2 is the block diagram of FPGA controller. It works in following mode: Basic process is the data's transfer of a block: Under the control of global clock, the address generator generates the 2864A's addresses. When Data input shift signal comes, 24 bit shift register offer the enable signals of these 24 6bit registers one by one. So these 144bit(24 pixels)display dat...
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