Abstract: A fuel-cell flow regulator is placed in a fuel cell having two entrances, each of which is formed at one of two sides of the fuel cell. The fuel cell is composed of a plurality of single cells, each of which includes a fuel inlet and a fuel passage in communication with the fuel inlet. The fuel passages jointly define a fuel tunnel in communication with all of the entrances. The flow regulator is located at the fuel tunnel and movable back and forth along the fuel tunnel.

Abstract: A method for designing and making an integrated circuit is described. That method utilizes statistical models of wire segments to accurately estimate the expected length of minimum-length, orthogonal wire segments within a block. From these estimates, the method accurately estimates an ratio between the horizontal and vertical routing resources required, termed the “H/V Demand Ratio.” From the H/V Demand Ratio, an accurate estimate of the height and width of the block may be determined. Thereafter, placement and routing may be performed quickly and accurately, thereby allowing the block to be designed and manufactured quickly and cost effectively. A method for designing an integrated circuit with efficient metal-1 resource utilization is also described.

Abstract: A method of fast analog layout migration from an original layout is disclosed. Various placement constraints, including topology, matching and symmetry are extracted from the schematic or netlist as well as the original layout. In addition, relative placement patterns are extracted from the original layout for matching and symmetry constraints. A constraint hierarchy tree can be built according to the constraints, and relative placement patterns are attached accordingly. By using the constraint hierarchy tree, multiple new placement results are efficiently explored that preserve the relative placement patterns for matching and symmetry constraints.

Abstract: Disclosed is a computer-implemented method to generate a placement for a plurality of device modules within an analog integrated circuit (IC) subject to a set of constraints. By building a constraint hierarchy tree according to the constraints, conflicts of constraints can be identified and resolved. Furthermore, placements can be generated based on the hierarchy tree through a bottom-to-top dimension optimization process and a top-down wire length optimization process. Furthermore, a graphical user interface can be used to display the tree, and the user can edit the tree visually and interactively.

Abstract: A placer produces a global placement plan specifying positions of cell instances and orientations of macros within an integrated circuit (IC) by initially clusterizing cell instances and macros to form a pyramidal hierarchy of blocks. Then the placer iteratively repeats the declusterization and routability improvement process from the highest level to the lowest level of the hierarchy. An objective function is provided in Cartesian coordinate for representing the position of each movable instance and in polar coordinate for representing the orientation of a macro relative to its the center. For each movable instance and each rotatable macro, its position or orientation is determined by conjugate gradient method to minimize total wire length. Finally, the placer uses a look-ahead legalization technique to rotate rotatable macros to legal orientations and move cell instances to legal positions in the end of global placement.

Abstract: A computer-implemented method to perform context-sensitive incremental design rule checking (DRC) for an integrated circuit (IC). An incremental DRC engine checks design rule violations between a set of environment shapes and a set of active shapes. If no design rule violations are found, the set of active shapes will be added into the set of environment shapes. Furthermore, the incremental DRC engine can be embedded into placement tools, routing tools, or interactive layout editing tools to check design rule violations and help generate DRC error free layouts.

Abstract: A fuel-cell flow regulator is placed in a fuel cell having two entrances, each of which is formed at one of two sides of the fuel cell. The fuel cell is composed of a plurality of single cells, each of which includes a fuel inlet and a fuel passage in communication with the fuel inlet. The fuel passages jointly define a fuel tunnel in communication with all of the entrances. The flow regulator is located at the fuel tunnel and movable back and forth along the fuel tunnel.

Abstract: A placer produces a global placement plan specifying positions of cell instances and orientations of macros within an integrated circuit (IC) by initially clusterizing cell instances and macros to form a pyramidal hierarchy of blocks. Then the placer iteratively repeats the declusterization and routability improvement process from the highest level to the lowest level of the hierarchy. An objective function is provided in Cartesian coordinate for representing the position of each movable instance and in polar coordinate for representing the orientation of a macro relative to its the center. For each movable instance and each rotatable macro, its position or orientation is determined by conjugate gradient method to minimize total wire length. Finally, the placer uses a look-ahead legalization technique to rotate rotatable macros to legal orientations and move cell instances to legal positions in the end of global placement.

Abstract: A placer produces a global placement plan specifying positions of cell instances to be interconnected by nets within an integrated circuit (IC) by initially clusterizing cell instances to form a pyramidal hierarchy of blocks and generating an initial global placement plan specifying a position of each block at a highest level of the hierarchy. The placer then declusterizes the global placement plan by replacing the highest level blocks with their component blocks and then improves the routability of the global placement plan by iteratively moving specified block positions in directions and by distances dynamically determined by analyzing the global placement plan and an objective function having a total wirelength term and having a bin density term reflecting density of blocks in specified areas (bins) of the IC.

Abstract: A method for designing and making an integrated circuit is described. That method utilizes statistical models of wire segments to accurately estimate the expected length of minimum-length, orthogonal wire segments within a block. From these estimates, the method accurately estimates an ratio between the horizontal and vertical routing resources required, termed the “H/V Demand Ratio.” From the H/V Demand Ratio, an accurate estimate of the height and width of the block may be determined. Thereafter, placement and routing may be performed quickly and accurately, thereby allowing the block to be designed and manufactured quickly and cost effectively. A method for designing an integrated circuit with efficient metal-1 resource utilization is also described.

Abstract: A multi-packing tree (MPT) macro placer. The MPT macro placer comprises reading input files in a LEF/DEF format, creating a k-level binary multi-packing tree comprising k branch nodes each corresponding to one level and k+1 packing sub-trees each corresponding to one of the nodes and comprising a group of macros, optimizing the multi-packing tree according to a packing result thereof, and generating output files in a DEF format.

Abstract: To generate a floorplan for an integrated circuit to be formed by a collection of modules interconnected by nets, the floorspace to be occupied by the integrated circuit is partitioned into regions and all of the modules are allocated among those regions. The regions are then iteratively partitioning into smaller progressively smaller regions with modules previously allocated any partitioned region allocated among the regions into which it was partitioned, until each region of the floorplan has been allocated no more than a predetermined maximum number of modules. A separate floorplan is then generated for each region. Neighboring regions are then iteratively merged to create progressively larger regions, until only a single region remains, wherein upon merging any neighboring regions to form a larger merged region, the floorplans of the neighboring regions are merged and refined to create a floorplan for the merged region.

Abstract: A placer produces a global placement plan specifying positions of cell instances to be interconnected by nets within an integrated circuit (IC) by initially clusterizing cell instances to form a pyramidal hierarchy of blocks and generating an initial global placement plan specifying a position of each block at a highest level of the hierarchy. The placer then declusterizes the global placement plan by replacing the highest level blocks with their component blocks and then improves the routability of the global placement plan by iteratively moving specified block positions in directions and by distances dynamically determined by analyzing the global placement plan and an objective function having a total wirelength term and having a bin density term reflecting density of blocks in specified areas (bins) of the IC.

Abstract: To generate a floorplan for an integrated circuit to be formed by a collection of modules interconnected by nets, the floorspace to be occupied by the integrated circuit is partitioned into regions and all of the modules are allocated among those regions. The regions are then iteratively partitioning into smaller progressively smaller regions with modules previously allocated any partitioned region allocated among the regions into which it was partitioned, until each region of the floorplan has been allocated no more than a predetermined maximum number of modules. A separate floorplan is then generated for each region. Neighboring regions are then iteratively merged to create progressively larger regions, until only a single region remains, wherein upon merging any neighboring regions to form a larger merged region, the floorplans of the neighboring regions are merged and refined to create a floorplan for the merged region.

Abstract: A multi-packing tree (MPT) macro placer. The MPT macro placer comprises reading input files in a LEF/DEF format, creating a k-level binary multi-packing tree comprising k branch nodes each corresponding to one level and k+1 packing sub-trees each corresponding to one of the nodes and comprising a group of macros, optimizing the multi-packing tree according to a packing result thereof, and generating output files in a DEF format.