Sagantec - Companion


	Accelerate the layout design process for memory, datapath, control logic, I/Os, and cell libraries
	Increase layout productivity by 2X – 10X
	Virtually eliminate DRC runs and significantly decrease LVS iterations
	Eliminate excessive polygon pushing – automatically compacts design to densest possible layout
	Leverage investment in existing design environment through seamless integration with Cadence Design Systems Virtuoso®/ Virtuoso® XL Layout Editor



	Companion works seamlessly with the Virtuoso® layout editor from Cadence Design Systems for rapid cell and IP development to accelerate custom design process and to significantly reduce the number of DRC and LVS iterations. A layout engineer does a rough, preliminary place and route with Virtuoso and then uses the 'compact' button on the Virtuoso tool bar. Companion examines the layout, repositions the polygons to fix DRC errors, places all edges on grid and further compacts the layout to render the placement and routing into a correct and optimized detailed physical design.


	Supports top-down or bottom-up design flows
	Automatic pitch-matching to pre-designed abutting cells
	Device sizes directly enforced from upstream design data
	Automatic grid adherence for routing terminals
	Preserves all design properties such as pin names, connectivity and text labels
	Preserves Cadence’s paths, Pcells and RODs
	Automatically applies complex design rules for deep submicron technologies
	Visual critical dimensions feedback indicates congested areas and the constraining elements
	Automatic optimal contact strapping for devices and well/substrate taps

Companion accelerates the interactive design creation or migration of full custom layout by combining the design expertise and skills of the layout designer with the power of Sagantec's compaction technology within the Cadence Design Systems' Virtuoso layout environment. Working in this environment, the layout designer can concentrate on placement and routing and getting a good architecture instead of measuring distances and trying to manually handle and satisfy all the complex rules of today's advanced technologies. These more mechanical and laborious tasks are left for Companion. It will take the tedious task of fixing all DRC violations in the layout and provide valuable layout critical dimension feedback. The integration and ease-of-use of Companion enable designers to focus on creating optimal full-custom layout and accomplish a quality result, fast.

Enhanced Productivity.

When the Companion's 'compact' button on the Virtuoso menu bar is pressed, the layout being edited is instantly compacted to the smallest possible area, while still conforming to the design rules of the fabrication technology. The layout is also instantly cleaned of all DRC violations, and congested areas that limit the layout's dimensions are highlighted. With Companion, physical layout designers can create design-rule correct, optimal complex full-custom layouts in a few hours instead of several days.

Companion significantly enhances the productivity of layout designers by allowing them to focus on creating denser layouts without concern for design rule violations. Layout designers using Companion report an immediate layout productivity increase ranging from 2X to 10X and a layout cell area decrease of 5% to 15%. These benefits become even more pronounced at deep submicron technologies (line width of 0.18 micron and smaller) where significantly more effort is required to accomplish a dense and correct layout in a reasonable time frame

Optimal Layouts

The full custom layout designer can quickly create a rough and loose preliminary place and route layout in Virtuoso followed by launching Companion by hitting the 'compact' button. Companion examines the preliminary layout and further compacts polygon edges, using Sagantec's polygon edge repositioning to render the placed and routed elements into an optimized physical design. In addition, Companion guides the designer to a denser layout by pointing out congested areas in the compacted layout. The result is a more optimal layout than can be achieved without numerous manual iterations.

Companion can be used effectively to design full-custom blocks, custom or standard cells and memory cells, as well as macro blocks. Leaf cells can be constructed completely from scratch. Or they can be drawn by migrating and modifying a previously designed database.

Companion Applications

Memory cells and generators with automatic pitch-matching
High performance/low power full-custom logic blocks
Mixed-signal blocks
Standard cell libraries
I/O cells

Unlike some traditional symbolic layout compaction tools that cannot read and handle existing polygon-based layout databases, Companion has no such limitation. The direct interface of Companion to the Design Framework II database ensures that all physical design properties, such as pin names, connectivity or text labels, are preserved. This makes Companion a highly versatile and integrated solution with unique capabilities for the creation of new, as well as modification and migration of existing full-custom layout.

Full Designer Control

For the creation of memory, datapath and standard cell libraries, designers can specify abutment relations for neighboring cells that are already present in the Design Framework II database. Pitch matching requirements for these cells are automatically maintained. Device sizes for each transistor can be directly read from the schematic corresponding to that layout.

Designers can exert full control over final layout by manually inserting spacing requirements and transistor W/L values to override design rules and schematic values. Companion can work directly on polygon-level layouts and can also preserve higher-level constructs such as sub-cells that can be handcrafted or generated by Pcells and RODs. At the same time, Companion maintains connectivity information for the Virtuoso Custom Router. Sub-cell preservation allows optimal compaction while maintaining the design hierarchy.

With the advent of recent automatic place and route flows for interactive custom layout, in many cases the router requires additional space to complete all connections. In such a flow, Companion is used to compact the layout after routing and thus gain up to 20% of the area. Additional features like path handling, support of net-dependent rules, window compaction, and keep-out areas make it easy to use these automatic place and route environments such as the Virtuoso Custom Designer. With this flow, Companion complements existing design methodology for full custom layout while significantly improving layout productivity.

Companion is compatible with the following third party software:

Cadence Virtuoso® version 4.4.x and higher.