Analog circuit shielding routing algorithm based on net classification

Abstract

Analog signals are more sensitive to crosstalk than digital signals, resulting in instability of analog circuits. To eliminate coupling, it is common practice to insert shielding wires on one or both sides of critical signals. In this paper, a novel analog circuit shielding routing algorithm based on net classification is proposed. Circuit performance requirements are transformed into geometric properties of nets according to the result of placement, and different shielding wire routing algorithms are designed to meet these geometric properties. A∗ algorithm is adopted to route the critical nets, and shielding wires are added at the same time. Maze algorithm is used to route the P/G nets and other general nets. Experimental results show that the router is efficient in routing and effective in reducing crosstalk. Although capacitive load and routing area increase, the resulting coupling is negligible and the circuit performance is significantly improved.∗