低SSN的机顶盒芯片DDR控制器的设计

DDR Controller Design for STB with Low SSN

低成本QFP封装的SSN效应是限制DDR接口传输速率的重要因素。根据图像数据翻转比特的分布统计,提出了基于数据重发的DDR控制器设计方法。本方法利用DDR芯片上的DM功能管脚将1次高数据比特翻转的写传输转化成2次低数据比特翻转的写传输。分析结果表明提出的方法能以较少的代价减少SSN。

The SSN with low cost QFP package inductor is one of the important causes which limit the DDR transfer rate of STB chip.In this paper,video data toggle situation is discussed and a data rewrite based DDR controller is proposed.This method changes a high data toggle rate write transaction into 2 low data toggle rate write transactions with DM signals of DDR chip.Simulation result shows that this method can reduce SSN with acceptable cost.