Abstract: The high-performance chip design has a larger design scale, higher frequency, more complex design data and reliability, and more signoff indicators under 7 nm and higher process nodes. Machine learning has been successfully applied in many fields, and complex chip design is a good field for applying machine learning. Cadence built the algorithm into the Innovus tool, and built the machine learning model by learning and modeling the chip design data to improve chip performance. A physical design process that applies machine learning to optimize latency is established to improve chip design performance. This paper presents a machining-learning-based physical design flow that optimizes delay to improve chip design performance. In orde to choose a better solution,,the effect of optimizing the cell delay,,net delay,cell and net delay separately on the design was discussed and analyisised in detail. Finally,,the solution is applied to another block design with more difficult design and higher performance requirements . To verifies the consistency of the flow,,a more comprehensive analysis is completed from the aspects of timing,power,,wire length,,etc.
Key words : machine learning;Innovus,;chip design,;physical design
0 引言
摩爾定律揭示了集成電路的集成度和技術(shù)節(jié)點的飛速發(fā)展,這使得芯片設(shè)計的復(fù)雜度和數(shù)據(jù)量快速上升,,尤其是芯片的物理設(shè)計更是涉及海量的數(shù)據(jù)和信息,,且運行時間和設(shè)計周期漫長,迭代一次的時間和資源代價很大,,這對設(shè)計師的經(jīng)驗與能力要求很高,。機器學(xué)習(xí)如今在各個領(lǐng)域都有廣泛的應(yīng)用,其能學(xué)習(xí)數(shù)據(jù)規(guī)律建立模型從而快速推斷結(jié)果[1],。如果能在物理設(shè)計中應(yīng)用機器學(xué)習(xí)挖掘設(shè)計規(guī)律,,且基于推斷的求解來進行物理設(shè)計,,可加速芯片設(shè)計。國內(nèi)外很多學(xué)者在此方面有了成功的研究,,包括PAN D Z等詳細介紹的在物理設(shè)計中應(yīng)用機器學(xué)習(xí)[2],。LI B使用機器學(xué)習(xí)由全局布線線預(yù)測詳細布線結(jié)果[3]。TSMC在物理設(shè)計中應(yīng)用機器學(xué)習(xí)的兩款芯片分別可使頻率提升40 MHz和減少20 000時鐘門控單元等[4],。