Abstract: To estimate a distribution of voltages or currents in the layers of a multi-layer circuit, an exemplary current flow in each layer is discretized into a number of current vector elements and at least one scalar charge element related to the charge associated with each current vector element. A first distribution of voltages induced in each circuit layer is determined from current vector elements in all of the circuit layers. A second distribution of voltages induced in each circuit layer is determined from the scalar charge elements in all of the circuit layers. For each circuit layer, the first and second distributions of voltages induced therein are combined to determine an actual distribution of voltages in the circuit layer.

Abstract: Integrated proof flow methods and apparatuses are discussed. Integrated proof flow refers to attempting both formal verification and nonformal verification. A coverage metric can be changed by both attempting formal verification and by attempting nonformal verification. Some embodiments of the present invention provide proof flow methods that integrate verification and nonformal verification (e.g., bounded verification, multi-point proof, and/or vector-based simulation) to prove one or more properties in a circuit design.

Abstract: The transmitter circuit architecture is disclosed based on a phase lock loop architecture and which uses a delta-sigma modulator with 2 point modulation. In order to restrict the bandwidth of the PLL, subsidiary analogue modulation is employed, which requires aligning with the delta-sigma modulation. Alignment of the modulation is accomplished by correction of the sensitivity of the PLL voltage controlled oscillator to modulation by correlating residual modulation in the PLL with the modulated signal input. The action of the modulation correlator trims the modulation and the PLL bandwidth without disturbing the normal operation of the transmitter, and allows the use of modulation bandwidths greater than the PLL bandwidth.

Abstract: Some embodiments of the invention provide a method of routing nets in a multi-layer integrated-circuit (“IC”) layout. For each particular net in a set of nets, the method specifies different spacing constraints for routing the particular net in different directions on the same layer. It then defines a particular route for each particular net in the set of nets, where the spacing between at least one particular route and an item adjacent to the route in the layout is different in the different directions on the same layer.

Abstract: Dependencies can be specified between jobs that are constituent to a unit of work, which are automatically determined or identified by processing a work request that defines the work. For example, a second job can be specified as depending on a first job meeting a particular condition. Furthermore, sub-works of the second job are not scheduled for execution until the first job has met the condition, thus allowing the second job to be placed into an active state. First, a work request is received, which specifies a first job that includes a first set of sub-works and a second job that includes a second set of sub-works. The work request is interpreted and processed to determine that the second job has the dependency on the first job. The first job is placed into an active state to enable the first sub-works to be scheduled for execution. The second job is placed in a pending state and it is determined whether the first job has met the condition.

Abstract: The present invention introduces methods, systems, and architectures for routing clock signals in an integrated circuit layout. The introduced clock signal clock signal structures are rendered with non Manhattan routing. In a first embodiment, the traditional recursive H clock signal structure is rendered after transforming the coordinates system such that a rotated recursive H clock signal structure is rendered. In another embodiment, a recursive Y structure is used to create a clock signal structure. The recursive Y structure may also be implemented in a rotated alignment. For clock signal redundancy, non Manhattan wiring may be used to create a clock signal mesh network.

Abstract: A system, method, computer program and article of manufacture for channel analysis. Channel analysis is a multi gigahertz capacity time domain circuit simulation which uses the impulse response of the channel to determine optimum filter settings and to produce wave form plots in a fraction of the time of circuit simulation.

Abstract: Some embodiments of the invention provide a method of decomposing a design layout. The method decomposes the layout into a tessellated graph with several edges. It then computes the capacity of the edges based on a interconnect line model that is used to connect elements in the design layout. The layout has two orthogonal coordinate axes. At least one interconnect line specified by the model is neither parallel nor perpendicular to the coordinate axes. Also, in some embodiments, some of the edges are neither parallel nor perpendicular to the coordinate axes.

Abstract: The present invention introduces novel methods of performing integrated circuit layout extraction. In the system of the present invention, complex resistance extraction problem is first broken down into a set of smaller extraction sub problems. Some of the smaller extraction sub problems may be handled by simple parametric models. For example, extracting the resistance from a straight section of interconnect wire may be performed by multiplying a known resistance per unit length by the length of the straight section of interconnect wire. For more complex resistance extraction sub problems, machine learning is used to build models.

Abstract: One embodiment of the invention is a method of specifying routes for a group of nets. The method identifies different routing solutions for the group of nets. It then selects the best routing solution.

Abstract: Disclosed are methods and systems for formulating a wirelength estimate that takes into account whether any of the routing directions are unavailable. Under certain circumstances, one or more of the routing layers may not be available for routing a wire. If this occurs, then the bounding box that is determined for performing the wirelength estimate would take into account the unavailability of the layer.

Abstract: A system for using machine learning based upon Bayesian inference using a hybrid Monte Carlo method to create a model for performing integrated circuit layout extraction is disclosed. The system of the present invention has two main phases: model creation and model application. The model creation phase comprises creating one or more extraction models using machine-learning techniques. First, a complex extraction problem is decomposed into smaller simpler extraction problems. Then, each smaller extraction problem is then analyzed to identify a set of physical parameters that fully define the smaller extraction problem. Then, for each of the smaller simpler extraction problems, complex mathematical models are created using machine learning techniques.

Abstract: A method and system for reducing test data volume in the testing of logic products such as integrated circuit chips. Test data loaded by a tester into the logic product to apply to portions of combinational logic circuitry therein in order to detect faults comprises “care” bits and “non-care” bits. The care bits target focal faults of interest in the logic circuitry being tested while the non-care bits do not. According to the invention, non-care bits in the test vector data are filled with repetitive background data to provide for a high degree of compressibility of the test vector data. A substantial portion of the care bits may also be set to a repetitive value and the original values later recovered.

Abstract: One embodiment of the invention is a recursive partitioning method that places circuit elements in an IC layout. This method initially defines a number of partitioning lines that divide an IC region into several sub-regions (also called slots). For a net in the region, the method then identifies the set of sub-regions (i.e., the set of slots) that contain the circuit elements (e.g., the pins or circuit modules) of that net. The set of sub-regions for the net represents the net's configuration with respect to the defined partitioning lines. Next, the placement method identifies attribute or attributes of a connection graph that models the net's configuration with respect to the partitioning lines. The connection graph for each net provides a topology of interconnect lines that connect the slots that contain the net's circuit elements. According to some embodiments of the invention, the connection graph for each net can have edges that are completely or partially diagonal.

Abstract: Some embodiments of the invention provide a method for pre-tabulating sub-networks. This method (1) generates a sub-network that performs a function, (2) generates a parameter based on this function, and (3) stores the sub-network in a storage structure based on the generated parameter. In some embodiments, the generated sub-network has several circuit elements. Also, in some embodiments, the generated sub-network performs a set of two or more functions. Some embodiments store each generated sub-network in an encoded manner. Some embodiments provide a method for producing a circuit description of a design. This method (1) selects a candidate sub-network from the design, (2) identifies an output function performed by the sub-network, (3) based on the identified output function, identifies a replacement sub-network from a storage structure that stores replacement sub-networks, and (4) replaces the selected candidate sub-network with the identified replacement sub-network in certain conditions.

Abstract: A method of analyzing a design of an electronic circuit includes tessellating the design into a grid of rectangles, selecting at least one rectangle as a first level parent rectangle, and generating a plurality of second level child rectangles based on the first level parent rectangle.

Abstract: Systems and methods for designing integrated circuits and for creating and using androgynous interfaces between electronic components of integrated circuits are disclosed. One preferred method of designing an integrated circuit includes several steps. In one step, a foundation block for the integrated circuit is specified, including specifying the locations of multiple androgynous interfaces in the integrated circuit. In another step, one or more component blocks to comprise the integrated circuit are identified for use. In another step, the component blocks to form a layout of the integrated circuit are positioned in a manner that minimizes connection distances between functional blocks and between functional blocks and the androgynous interfaces. In another step, the androgynous interfaces are set to perform as targets (slaves) or initiators (masters) based on the layout.

Abstract: A method of analyzing a design of an electronic circuit uses slices. The method includes generating one or more slices, each slice comprising a contiguous region of the design, and generating an set comprising one or more bins for each slice. A search for an object may be performed by determining a search area, and identifying slices containing at least a portion of the search area. For each identified slice, each object within the search area is associated with one of the bins of the set for the slice.

Abstract: Disclosed is an improved approach for maintaining the structures for objects in a layout. A single type of structure is maintained that can be used to store or track a polygon of any shape, as long as the shape possesses a supported number of sides. The structure is capable of supporting irregular polygons or objects having angled edges. In one approach, the structure maintains information about each polygon as if that polygon is an octagon. Therefore, any polygon having eight or less orthogonal or diagonal sides can be supported using this structure.

Abstract: Some embodiments of the invention provide a method of routing nets in a multi-layer integrated-circuit (“IC”) layout. For a particular net, the method specifies widths for routing the particular net in different directions on the same layer. It then defines a particular route for the particular net, where the route has different widths in the different directions on the same layer.