Abstract: Technology is disclosed herein that provides for modifying a circuit design to reduce the potential occurrence of single event upset errors during operation of a device manufactured from the synthesized design. After a circuit design has been synthesized to a particular abstraction level, a static timing analysis procedure is run on the design. The slack values for paths within the design are determined based upon the static timing analysis procedure. Subsequently, delays are added to selected paths within the design based upon the slack values.

Abstract: Disclosed are representative embodiments of methods, apparatus, and systems for voltage-related analysis of layout design data. According to embodiments of the disclosed technology, voltage association data objects are generated for drawn layers in a net of a layout design and voltage values or ranges of voltage values associated with the net are collected. The voltage values or ranges of voltage values are then associated with the voltage association data objects. A voltage-related analysis may be performed by searching the voltage association data objects according to a predetermined criterion.

Abstract: The amount of analysis performed in determining the validity of a property of a digital circuit is measured concurrent with performance of the analysis, and provided as an output when a true/false answer cannot be provided e.g. when stopped due to resource constraints. In some embodiments, a measure of value N indicates that a given property that is being checked will not be violated within a distance N from an initial state from which the analysis started. Therefore, in such embodiments, a measure of value N indicates that the analysis has implicitly or explicitly covered every possible excursion of length N from the initial state, and formally proved that no counter-example is possible within this length N.

Abstract: A system and method is disclosed in an emulation environment that dynamically remaps user designs. In one embodiment, a request is received to load an integrated circuit design to be emulated in a desired partition within the emulator. The emulator automatically determines the availability of the partition requested. If the partition is not available, the design is dynamically remapped to a different partition that is available. In another embodiment, clocks associated with the integrated circuit design are also dynamically remapped. In yet another embodiment, the user can control the size of the partitions (e.g., the number of printed circuit boards in a partition).

Abstract: Disclosed herein are exemplary embodiments of a so-called “X-press” test response compactor. Certain embodiments of the disclosed compactor comprise an overdrive section and scan chain selection logic. Certain embodiments of the disclosed technology offer compaction ratios on the order of 1000×. Exemplary embodiments of the disclosed compactor can maintain about the same coverage and about the same diagnostic resolution as that of conventional scan-based test scenarios. Some embodiments of a scan chain selection scheme can significantly reduce or entirely eliminate unknown states occurring in test responses that enter the compactor. Also disclosed herein are embodiments of on-chip comparator circuits and methods for generating control circuitry for masking selection circuits.

Abstract: Aspects of the invention relate to techniques for chain fault diagnosis based on dynamic circuit design partitioning. Fan-out cones for scan cells of one or more faulty scan chains of a circuit design are determined and combined to derive a forward-tracing cone. Fan-in cones for scan cells of the one or more faulty scan chains and for failing observation points of the circuit design are determined and combined to derive a backward-tracing cone. By determining intersection of the forward-tracing cone and the backward-tracing cone, a chain diagnosis sub-circuit for the test failure file is generated. Using the process, a plurality of chain diagnosis sub-circuits may be generated for a plurality of test failure files. Scan chain fault diagnosis may then be performed on the plurality of chain diagnosis sub-circuits with a plurality of computers.

Abstract: In one embodiment, a method for performing an analysis of a synthesized clock tree can include: displaying a plurality of variation parameters and one or more analysis values on a display screen; accepting a first signal from a user input device to select one of the variation parameters; accepting a second signal from a user input device to select one or more of the analysis values; and displaying a plurality of pins from the synthesized clock tree with the selected variation parameter and the selected one or more analysis values on the display screen.

Abstract: A method for applying test patterns to scan chains in a circuit-under-test. The method includes providing a compressed test pattern of bits; decompressing the compressed test pattern into a decompressed test pattern of bits as the compressed test pattern is being provided; and applying the decompressed test pattern to scan chains of the circuit-under-test. The actions of providing the compressed test pattern, decompressing the compressed test pattern, and applying the decompressed pattern are performed synchronously at the same or different clock rates, depending on the way in which the decompressed bits are to be generated. A circuit that performs the decompression includes a decompressor such as a linear finite state machine adapted to receive a compressed test pattern of bits. The decompressor decompresses the test pattern into a decompressed test pattern of bits as the compressed test pattern is being received.

Abstract: Embodiments of methods, apparatus, and systems for extracting impedance for a circuit design are disclosed herein. Some of the disclosed embodiments are computationally efficient and can accurately compute the frequency-dependent impedance of VLSI interconnects and/or intentional inductors in the presence of multi-layer conductive substrates. In certain embodiments, the resulting accuracy and CPU time reduction are a result of a Green's function approach with the correct quasi-static limit, a modified discrete complex image approximation to the Green's function, and a continuous dipole expansion to evaluate the magnetic vector potential at the distances relevant to VLSI interconnects and intentional inductors.

Abstract: Aspects of the invention relate to techniques of using two-dimensional scan architecture for testing and diagnosis. A two-dimensional scan cell network may be constructed by coupling input for each scan cell to outputs for two or more other scan cells and/or primary inputs through a multiplexer. To test and diagnose the two-dimensional scan cell network, the two-dimensional scan cell network may be loaded with chain patterns and unloaded with corresponding chain test data along two or more sets of scan paths. Based on the chain test data, one or more defective scan cells or defective scan cell candidates may be determined.

Abstract: A decoder for decoding an address having a plurality of bits ranging from a first address bit a1 to a last address bit aN, each address bit being either true or false is provided that includes a pre-charge circuit adapted to pre-charge a dynamic NOR node and a dynamic OR node and then allow the pre-charged dynamic NOR node and pre-charged dynamic OR node to float; a plurality of switches coupled between the dynamic NOR node and ground, each switch corresponding uniquely to the address bits such that the switches range from a first switch corresponding to a1 to an nth switch corresponding to aN, wherein any switch corresponding to a true address bit is configured to turn on only if its corresponding address bit is false, and wherein any switch corresponding to a false address bit is configured to turn on only if its corresponding address bit is true.

Abstract: This application discloses a voltage analysis tool to perform a static power aware analysis on a circuit design without having to simulate the circuit design. The voltage analysis tool can determine a set of components in the circuit design corresponds to a design pattern representing a voltage-transition device, and set an output voltage for the set of components based, at least in part, on characteristics of the voltage-transition device. The voltage analysis tool can propagate the output voltage to other portions of the circuit design, and determine whether the portions of the circuit design receiving the output voltage have a rule violation.

Abstract: Aspects of the invention relate to techniques for estimating power and thermal profiles for an integrated circuit design. With various implementations of the invention, a group of devices is identified in a netlist based on information of the group of devices. The netlist may be a schematic netlist or a layout netlist extracted from a layout design. Power consumption information for the group of devices is determined based on device parameters for the group of devices and a lookup table. The determined power consumption information is then associated with layout location information. A thermal profile may then be estimated based on the power consumption information.

Abstract: Aspects of the invention relate to techniques for adaptive clock management in emulation. A clock suspension request signal, indicating when a suspension of design clock signals in an emulator is needed, is generated based on activity status information of the emulator with one or more emulator resources such as software environment. A clock suspension allowance signal, indicating whether a suspension of design clock signals is permitted considering dynamic targets in the emulator, is generated based on slack information related to one or more clock signals associated with one or more dynamic targets of the emulator. Based on the clock suspension request signal and the clock suspension allowance signal, a clock suspension signal is generated for enabling temporary design clock suspensions.

Abstract: Aspects of the invention relate to techniques for determining pattern optical similarity in lithography. Optical kernel strength values for a first set of layout features and a second set of layout features are computed first. Based on the optical kernel strength values, optical similarity values between the first set of layout features and the second set of layout features are then determined. Subsequently, calibration weight values for the first set of layout features may be determined based on the optical similarity values, which, along with the first set of layout features, may be employed to calibrate lithography process model parameters.

Abstract: Aspects of the invention relate to techniques for using retiming to reduce circuit switching activity. Switching activity values at output ports of circuit elements of a circuit design are first computed based on switching activity values at input ports of the circuit elements and scaling factors associated with the circuit elements. Based on the switching activity values at the output ports of the circuit elements, one or more regions of the circuit design for retiming are identified. Retiming location information is then determined for the one or more regions. Finally, the identified one or more regions are then retimed to reduce switching activity based on the retiming location information.

Abstract: Techniques for reducing the number of shots required by a radiation beam writing tool to write a pattern, such as fractured layout design, onto a substrate. One or more apertures are employed by a radiation beam writing tool to write a desired pattern onto a substrate using L-shaped images, T-shaped images, or some combination of both. By reducing the number of shots required to write a pattern onto a substrate, various implementations of the invention may reduce the write time and/or write complexity of the write process.

Abstract: Various aspects of the present invention relate to techniques of measuring delays between edges of signals of a circuit. Alternating signals, synchronous to a first clock, are supplied to a plurality of nodes of the circuit. First samples of a plurality of signals associated with the alternating signals are captured using a first capture clock, of which sampling instants are synchronous to a second clock. Second samples of the first samples are then captured using a second capture clock, of which sampling instants are also synchronous to the second clock. The captured second samples are conveyed via a shift register to a plurality of modulo counters. The measured signal delay includes a timing skew associated with the first clock and a timing skew of the first capture clock but not a timing skew of the second capture clock.

Abstract: Various embodiments provide for the determination of a test set that satisfies a coverage model, where portions of the search space need not be searched in order to generate the test set. With various embodiments, a search space defined by a set of inputs for an electronic design and a coverage model is identified. The search space is then fractured into subspaces. Subsequently, the subspaces are solved to determine if they include at least one input sequence that satisfies the coverage constraints defined in the coverage model. The subspaces found to include at least one input sequence that satisfies these coverage constraints, are then searched for unique input sequences in order to generate a test set. Subspaces found not to include at least one input sequence that satisfies the coverage constraints may be excluded from the overall search space.

Abstract: Aspects of the invention relate to techniques for determining the electromigration features corresponding to layout design data. According to various examples of the invention, a circuit design is analyzed to determine voltages of nodes in an interconnect tree. From the voltages of the nodes, current density values and current directions for the segments of the interconnect tree are determined. Based on the current density values and the current directions, hydrostatic stress values for the nodes are computed under a steady-state condition and conservation of the conductive material within the interconnect tree. The electromigration susceptibility of the interconnect tree is then determined based on the computed hydrostatic stress values.