| Title | Escape Routing of Differential Pairs Considering Length Matching |
| Author | *Tai-Hung Li, Wan-Chun Chen, Xian-Ting Cai, Tai-Chen Chen (National Central University, Taiwan) |
| Page | pp. 139 - 144 |
| Keyword | PCB, Routing, Differential Pair, Length Matching, skew |
| Abstract | The escape routing problem for PCB designs has been extensively studied in literature. Although industrial tools and few studies have worked on the escape routing of differentials pairs, the routing solutions are not good enough by previous methods. In this paper, we propose an escape routing approach of differential pairs considering length matching. The approach includes two stages. The first stage is to find min-cost median points which connect two pins by minimum and equal wire lengths while the second stage is adopted a network-flow approach with min-cost max-flow to simultaneously route all differential pairs. Experimental results show that our approach can efficiently and effectively obtain length-matching differential pairs with significant reduction in maximum and average differential-pair skews. |
| Title | An Any-Angle Routing Method using Quasi-Newton Method |
| Author | *Yukihide Kohira (The University of Aizu, Japan), Atsushi Takahashi (Osaka University, Japan) |
| Page | pp. 145 - 150 |
| Keyword | PCB routing, package routing, any-angle routing, quasi-Newton method |
| Abstract | In this paper, we propose a routing method which solves an any-angle gridless routing problem by formulating the problem by non-linear programming which is solved by quasi-Newton method. Our proposed method minimizes the total wire length or the total length error while satisfying constraints such as the separation for a route and an obstacle, the separation for two routes, and the angle of bend in a route. Experiments show that the proposed method is effective to obtain any-angle gridless routes in short computational time. |
| Title | Linear Optimal One-Sided Single-Detour Algorithm for Untangling Twisted Bus |
| Author | Tao Lin, *Sheqin Dong (Tsinghua University, China), Song Chen, Satoshi Goto (Waseda University, Japan) |
| Page | pp. 151 - 156 |
| Keyword | linear, optimal, untangling, Twisted Bus |
| Abstract | We considered the one-sided single-detour untangling twisted nets problem for printed circuit board bus routing. A previous optimal dynamic programming based O(n3) algorithm was proposed in a previous work, where n is the number of nets. In this paper, we propose an optimal O(n) untangling algorithm without considering capacity, and this algorithm is further modified to consider capacity with very little overhead. Experimental results show that our algorithm runs much faster than the previous work due to its low time complexity. |
| Title | LEMAR: A Novel Length Matching Routing Algorithm for Analog and Mixed Signal Circuits |
| Author | *Hailong Yao, Yici Cai, Qiang Gao (Tsinghua University, China) |
| Page | pp. 157 - 162 |
| Keyword | Analog and mixed signal circuits, Length matching, detailed routing |
| Abstract | Enabled by the heterogeneous integration in modern System-
On-Chips (SOCs), the design automation for analog and mixed signal
circuit components in SOCs is attracting increasing interests. Matching constraints for specific analog signals are critical for correct functionalities. This paper presents a novel single-layer detailed routing algorithm with the length matching constraint, called LEMAR. LEMAR features an innovative routing model for partitioning the routing layout for wire detouring, effective detouring patterns according to the geometric shapes of the partitioned tiles, an enhanced A*-search algorithm along with the
backtrack technique for finding the routing path, and an iterative rip-up and reroute procedure for finding the feasible routing solution with the matching constraint. Experimental results are promising and show that LEMAR is both effective and efficient. |