Abstract: A computer-implemented method for verifying impedance of a signal line in an electrical circuit layout includes reading a desired impedance value for a signal line and identifying the signal line in a circuit design database. A window is established around the signal line in which circuit elements will be included in an impedance calculation for the signal line. The impedance of the signal line is calculated based on the circuit elements inside the window. The signal line is flagged if the calculated impedance differs from the desired impedance value.

Abstract: A computer-implemented method for adjusting signal via impedance includes identifying a signal via in a circuit design database. The signal via is flagged as having an impedance error. A window is established around the signal via, with the window lying on a single layer. Only vias in the window may be adjusted to minimize the impedance error. At least one via in the window is adjusted to minimize said impedance error.

Abstract: In one aspect, techniques are disclosed for identifying and notifying a circuit designer of signal traces in an integrated circuit design that are closer to each other than a proximity threshold. It is desirable that signal traces be separated from each other by at least the proximity threshold to reduce inter-signal crosstalk to an acceptable level. Such notification may occur either dynamically (while the circuit designer is designing the circuit) or through a report generated after the circuit design has been generated. In another aspect, techniques are disclosed for identifying and notifying the circuit designer of the signal traces that are closest to a reference signal trace. Such notification may provide the circuit designer with feedback about regions in the circuit design which are congested and which may therefore produce an unacceptable level of crosstalk.

Abstract: A method is provided for evaluating via signal coupling in an electronic design (e.g., a package design). In the method, one or more via signal coupling rules are formulated. One or more via pairs designed to carry differential signals are then processed to determine whether the inter-via spacing between the via pairs violates the via signal coupling rules. An indicator (e.g., a DRC and/or a report) is generated to identify violated via signal coupling rules. Processing of the electronic design may be scoped according one or a group of signal nets, or one or a group of levels of the package design.

Abstract: A method is provided for evaluating signal deviations in an electronic design (e.g., a package design), including the steps of: formulating one or more signal deviation rules; processing the electronic design to determine whether the signal deviations violate the signal deviation rules; and generating an indicator (e.g., a DRC and/or report) associated with the electronic design to identify violated signal deviation rules. Processing of the electronic design may be scoped according one or a group of signal nets.

Abstract: A method evaluates signal trace discontinuities in an electronic design of the type having one or more traces. The method includes the steps of formulating one or more trace discontinuity rules, processing the electronic design to determine whether the traces violate the trace discontinuity rules, and generating an indicator (e.g., a DRC) associated with the electronic design to identify violated trace discontinuity rules. Each level, each signal net, or a group of signal nets may be evaluated, for example, to ensure compliance with the trace discontinuity rules.

Abstract: A method and software product evaluate vias in an electronic design. One or more via sufficiency rules are formulated, and then the electronic design is processed to determine whether the vias of the electronic design violate the via sufficiency rules. In the event of a violation, one or more indicators are generated to identify vias that violate the via sufficiency rules. The indicators are visual indicators (e.g., via insufficiency DRCs) on a graphical user interface, and/or a textual report summarizing violations.

Abstract: A method is provided for evaluating trace signal coupling in an electronic design (e.g., a package design). In the method, one or more trace signal coupling rules are formulated. One or more trace pairs designed to carry differential signals are then processed to determine whether the inter-trace spacing between the trace pairs violates the trace signal coupling rules. An indicator (e.g., a DRC and/or a report) is generated to identify violated trace signal coupling rules. Processing of the electronic design may be scoped according one or a group of signal nets, or one or a group of levels of the package design.

Abstract: A method and software product evaluate vias, per pad, in an electronic design. One or more via per pad rules are formulated, and then the electronic design is processed to determine whether the vias of the electronic design violate the via per pad rules. In the event of a violation, one or more indicators are generated to identify vias that violate the via per pad rules. The indicators are visual indicators (e.g., via per pad DRCs) on a graphical user interface, and/or a textual report summarizing violations.

Abstract: Techniques are disclosed for verifying the proximity of signal return paths (e.g., ground metal or power) to signal traces in an integrated circuit package design. A package designer creates the package design using a package design tool. A proximity verifier verifies that there is a signal return path within a predetermined threshold distance of each specified signal trace in the package layers directly above and/or below the signal trace. The proximity verifier may notify the package designer of any signal traces which are not sufficiently close to signal return paths, such as by providing visual indications of such signal traces in a graphical representation of the package design. In response, the package designer may modify the package model to ensure that all signal traces are sufficiently close to signal return paths.

Abstract: Techniques are disclosed for automatically synthesizing information from a plurality of computer-readable integrated circuit package models. In one embodiment, each of the plurality of package models contains information descriptive of a distinct package. Such information may include, for example, intra-package path lengths and/or propagation delays of signal nets in the modeled packages. Techniques are disclosed for automatically synthesizing such information to produce, for example, aggregate path lengths and/or propagation delays of the signal nets across all of the modeled packages. Such synthesis may be performed even when the package models use mutually inconsistent signal net naming conventions and the modeled packages are composed of different materials. Techniques are also disclosed for providing information to the package designer to assist the package designer in improving the design of the package models.

Abstract: Techniques are disclosed for automatically synthesizing information from a plurality of computer-readable integrated circuit package models. In one embodiment, each of the plurality of package models contains information descriptive of a distinct package. Such information may include, for example, intra-package path lengths and/or propagation delays of signal nets in the modeled packages. Techniques are disclosed for automatically synthesizing such information to produce, for example, aggregate path lengths and/or propagation delays of the signal nets across all of the modeled packages. Such synthesis may be performed even when the package models use mutually inconsistent signal net naming conventions and the modeled packages are composed of different materials. Techniques are also disclosed for providing information to the package designer to assist the package designer in improving the design of the package models.

Abstract: Techniques are disclosed for verifying the proximity of signal return paths (e.g., ground metal or power) to signal traces in an integrated circuit package design. A package designer creates the package design using a package design tool. A proximity verifier verifies that there is a signal return path within a predetermined threshold distance of each specified signal trace in the package layers directly above and/or below the signal trace. The proximity verifier may notify the package designer of any signal traces which are not sufficiently close to signal return paths, such as by providing visual indications of such signal traces in a graphical representation of the package design. In response, the package designer may modify the package model to ensure that all signal traces are sufficiently close to signal return paths.

Abstract: In one aspect, techniques are disclosed for identifying and notifying a circuit designer of signal traces in an integrated circuit design that are closer to each other than a proximity threshold. It is desirable that signal traces be separated from each other by at least the proximity threshold to reduce inter-signal crosstalk to an acceptable level. Such notification may occur either dynamically (while the circuit designer is designing the circuit) or through a report generated after the circuit design has been generated. In another aspect, techniques are disclosed for identifying and notifying the circuit designer of the signal traces that are closest to a reference signal trace. Such notification may provide the circuit designer with feedback about regions in the circuit design which are congested and which may therefore produce an unacceptable level of crosstalk.

Abstract: Techniques are disclosed for verifying the proximity of ground vias to signal vias in an integrated circuit package design. A package designer creates the package design using a package design tool. A proximity verifier verifies that there is a ground via within a predetermined threshold distance of each specified signal via in the package design. The proximity verifier may notify the package designer of any signal vias which are not sufficiently close to ground vias, such as by providing visual indications of such signal vias in a graphical representation of the package design displayed on a display monitor. In response, the package designer may modify the package model to ensure that all signal vias are sufficiently close to ground vias. The proximity verifier may be implemented as a design rule which may be executed automatically and in real-time by the package design tool.

Abstract: Techniques are disclosed for automatically synthesizing information from a plurality of computer-readable integrated circuit package models. In one embodiment, each of the plurality of package models contains information descriptive of a distinct package. Such information may include, for example, intra-package path lengths and/or propagation delays of signal nets in the modeled packages. Techniques are disclosed for automatically synthesizing such information to produce, for example, aggregate path lengths and/or propagation delays of the signal nets across all of the modeled packages. Such synthesis may be performed even when the package models use mutually inconsistent signal net naming conventions and the modeled packages are composed of different materials. Techniques are also disclosed for providing information to the package designer to assist the package designer in improving the design of the package models.