基于FPGA的大屏幕全彩LED扫描控制器设计

Design of Scan Controller in Large LED Screen Based on FPGA Circuit

介绍了一种以FPGA可编程逻辑器件为设计平台的、采用大屏幕全彩LED显示屏进行全彩灰度图像显示的扫描控制器实现方案。经过对"19场扫描"理论灰度实现原理的分析,针对采用该方法实现的全彩LED显示屏刷新频率受串行移位时钟限制的缺点,提出了一种新式的实现高阶灰度显示的逐位点亮控制方法,在进行FPGA电路设计中采用单独的计数器来控制屏幕的刷新频率,使全彩LED显示屏的设计在LED的发光效率和刷新率之间的调整更加灵活。最后,根据大屏幕全彩LED显示屏的设计要求,结合本文讨论的灰度控制方法,给出了FPGA屏体扫描控制器的内部电路实现结构框架。

An approach to implement the full color image display on the large size LED screen is introduced. The ＇nineteen-field scan＇ theory is firstly analyzed, and it is found that the refresh frequency is restricted by the serial shift clock. Then, in order to improve the insufficiency of ＇nineteen-field scan＇ method, a new grey control method based on the theory of ＇turn on one by one＇ is discussed. The refresh frequency is controlled by a single counter in the design of the FPGA circuit, which makes the adjustment between the luminescence efficiency and the refresh rate more flexible. Finally, the system is successfully realized by the design of the FPGA large LED screen. The internal circuit structure is controller to meet the requirement of the full color demonstrated.