Shape-based router brings automatic custom net routing to IC Compiler users

March 25, 2013 // By Graham Prophet
Synopsys has announced the Galaxy Custom Router, to work with its IC Compiler Custom solution, and that adds new analog and mixed-signal routing technology, with automated routing for custom nets, such as shielded buses, and differential pairs: the tool supports 20-nm, and smaller, process technology rules, including double-patterning.

Added to the Galaxy Platform, the Galaxy Custom Router provides automatic routing for complex high-speed digital and mixed-signals nets that require carefully crafted, high-quality layouts, such as shielded buses or nets, differential pairs, twisted pairs and matched resistance and capacitance (RC) routing. This new shape-based router delivers, Synopsys claims, two to five times productivity improvements over manual efforts and is ready for use with advanced designs by offering support for 20-nanometer (nm) and smaller process technology design rules, including double-patterning.

The router enables IC Compiler users to create high-quality routing patterns for difficult routing tasks, such as differential pair routing, shielded routing (including bus and differential pair shielding), matched RC routing, river routing and point-to-point coaxial routing. River routing is where each net route is completed in a single layer; you can use multiple layers in river routing to stack routes through congested channels, each individual net stays on one layer. Other features include complex signal shielding of river-routed paths in parallel, tandem and coaxial layouts; differential-pair (see picture), star and balanced routing; matched routing, clock tree routing; shielding in parallel, tandem, and coaxial modes of buses, differential pairs and scalar nets; and resistance, capacitance (RC) and length matching. You can place shielding wires around signal wires in interleaved or double-interleaved styles, that is with one or two shield wires between the bit nets.

The router supports features for analogue block-level routing, including matched route, differential pair, triplet, star and balanced routing. These routes may also be shielded or twisted using several different styles. Routes may be matched either by length or by resistive and capacitive values. For differential pair or triplet routing, two or three pins are routed together, according to the spacing constraint, with matched length: pairs can be shielded and/or twisted, with the option of a 90-degree or 45-degree twist. Parallel shielding placed shield wires either side of a signal line: tandem shielding places them above and