By Topic

An efficient cut-based algorithm on minimizing the number of L-shaped channels for safe routing ordering

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

1 Author(s)
Jin-Tai Yan ; Dept. of Comput. Sci. & Inf. Eng., Chung Hua Univ., Hsinchu, Taiwan

Because definition of L-shaped channels in a floorplan graph breaks all the cyclic precedence constraints in a building block layout, routing space in a layout can be fully separated and defined as straight and L-shaped channels to guarantee a safe routing ordering. However, L-shaped channel routing is more difficult than straight channel routing. Hence, it is necessary for the completion of detailed routing to minimize the number of L-shaped channels in channel definition of a floorplan graph. In this paper, based on a geometrical topology of a floorplan graph and precedence relations in a channel precedence graph, cuts in a floorplan graph are classified into S-cuts, redundant L-cuts, balanced L-cuts, nonminimal L-cuts, noncritical L-cuts and critical L-cuts. An efficient cut-based algorithm on minimizing the number of L-shaped channels in channel definition of a floorplan graph is proposed, and the time complexity of our cut-based algorithm is proved to be in O(n) time, where n is the number of line segments in a floorplan graph. Finally, several examples have been tested on Dai's algorithm [1985], Cai's algorithm [1993] and our cut-based algorithm, respectively. The experimental results show that our cut-based algorithm defines fewer L-shaped channels in a floorplan graph than Dai's algorithm and Cai's algorithm to guarantee a safe routing ordering

Published in:

Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on  (Volume:18 ,  Issue: 10 )