摘要: |
随着CPU、DSP等器件的处理速度迅速提高,对内存的速度和各方面的需求迅速增加。早期的SDRAM工作频率发展到133MHz已到极限,成为系统性能的瓶颈。DDR(双倍数据率)技术随之应运而生,目前DDR4的性能已经可以达到3200Mbps级别。DDR PHY作为存储控制器和DRAM颗粒物理接口之间的通用接口,是制约DDR读写速度提升的关键。本文以TSMC 28nm工艺的DDR PHY设计为例,结合Innovus工具,在描述流程之外,重点研究解决了后端物理设计中时序路径的时间预算、延时优化、路径对齐等问题。最后该DDR PHY在一款工业级DSP中成功集成,并且板级测试结果表明其物理设计结果达到指标要求。 |
关键词: DDR PHY 物理设计 Innovus 时间预算 延时优化 路径对齐 |
DOI:DOI:10.3969/j.issn.1672-2337.2020.04.018 |
分类号:TN47 |
基金项目: |
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Physical Design Methods of a 28nm DDR PHY Based on Innovus |
WANG Qiushi, ZHANG Jie, MENG Shaopeng
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The 38th Research Institute of China Electronics Technology Group Corporation, Hefei230088, China
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Abstract: |
With the rapid increase in the processing speed of CPU and DSP, the demand for speed and other various aspects of memory has increased rapidly. The early SDRAM operating frequency has developed to the limit of 133MHz, which became the bottleneck of system performance. Afterwards, DDR (double data rate) technology came into being, and the performance of DDR4 can reach 3200Mbps. DDR PHY, as a common interface between the memory controller and high-speed DDR DRAM device, is the key to restricting the read-write speed. This paper describes physical design methods of a 28nm DDR PHY based on Innovus, with focus on timing budget, delay optimization and path balancing. Finally, this DDR PHY is integrated into an industrial DSP. The board-level test results show that the DDR PHY performance meets the requirements. |
Key words: DDR PHY physical design Innovus timing budget delay optimization path balancing |