提出一种基于线网分类的模拟电路自动布线方法,并设计实现了一种基于线网分类的模拟电路布线器NCARouter.基于模拟电路性能要求,布线器中的线网被分为关键线网、普通线网和电源/地线网3种类型.同时,模拟电路的性能约束被转化为线网的属性描述,包括几何约束(如对称)、电学约束(如匹配)、寄生参数描述等.此外,针对不同类型的线网,该布线器使用了不同的布线算法,以满足总体性能约束.实验结果表明,该布线器不仅能很好地完成布线,还能确保满足模拟电路各种性能要求.
A new approach, called net classification method, is proposed, and by which a netclassification-based analog IC router (NCARouter) is implemented. According to the performance requirement of analog circuits, nets are classified into three main types: critical nets, general nets and power/ground nets. At the same time, all the circuit performance constraints are converted into some kinds of characteristics descriptions of nets, including geometrical constraints such as symmetry, electrical constraints such as matching, and parasitic parameters, etc. Besides, different types of nets could be routed by corresponding algorithms, in order to meet their performance requirements. Experimental results show that the new router can not only route well, but also satisfy the performance of analog circuits.