Abstract: A system includes a memory that stores instructions and receives a circuit netlist, and includes a processing unit that accesses the memory and executes the instructions. The instructions include an EDA application that includes a test-point flop allocation module that is configured to evaluate the circuit netlist to determine compatibility of the test-point nodes in the circuit netlist. The test-point flop allocation module can further allocate each of the test-point flops to a test-point sharing group comprising a plurality of compatible test-point nodes. The EDA application also includes a circuit layout module configured to generate a circuit layout associated with the circuit design, the circuit layout comprising the functional logic and scan-chains comprising the test-point flops allocated to the test-point sharing groups in response to the circuit netlist. The circuit layout is employable to fabricate an integrated circuit (IC) chip.

Abstract: An IC chip test engine selects an instrument of an IC design based on an instrument access script, wherein the selected instrument comprises an IP block and a test data register (TDR) logically arranged upstream from the IP block. The IC chip test engine can also identify a set of SIBs gating access to the selected instrument and select a scan chain for operating the set of SIBs to control access to the selected instrument. The IC chip test engine augments the scan chain with data to cause at least a furthest downstream SIB of the set of SIBs that gates access to the selected instrument to transition to an opened state. The IC chip test engine can generate a set of load vectors for the scan chain to load the TDR of the selected instrument with data to apply a respective test pattern to the IP block.

Abstract: A scan chain engine can determine a set number of EXTEST scan chains for the IP block and based on a predetermined maximum number of EXTEST wrapper cells per EXTEST scan chain. The scan chain engine iteratively executes partitioning on the IP block to generate a set of partitions. Each partition in the set of partitions has a number of EXTEST wrapper cells that does not exceed the maximum number of EXTEST wrapper cells per EXTEST scan chain. The scan chain engine selectively merges partitions of the set of partitions to form a set of populated partitions that each include an EXTEST wrapper cell. The number of partitions is equal to the set number of EXTEST scan chains for the IP block. The scan chain engine generates wire paths connecting EXTEST wrapper cells of each populated partition to construct the set number of EXTEST scan chains for the IP block.

Abstract: Methods and design system for generating 2-dimensional distribution architecture for testing integrated circuit design that utilizes double grid to minimize interdependencies between grid cells and the associated functional logic to facilitate the a physically efficient scan of integrated circuit designs, that simultaneously minimizes required test application time (“TAT”), test data volume, tester memory and cost associated with design for test (“DFT”), while also retaining test coverage. An additional grid parallel to a 2-dimensional XOR grid may be implemented that improves the quality of test coverage by optimally adding additional data inputs which decreases correlations between grid cells. A column spreader may feed data into column wires and row spreader may feed data into column wires. The double grid allows data to be fed into two wires, row and column, respectively, which provides twice as much stimulus data in each direction, without significantly increasing the wiring used to build the grid.

Abstract: Systems, methods, media, and other such embodiments described herein relate to improved operation of test devices which verify circuit operations. One embodiment involves accessing a circuit design comprising a plurality of instances of one or more blocks, where each block of the one or more blocks is associated with a corresponding block test pattern comprising one or more test subpatterns. Each corresponding block test pattern is processed to identify independent test subpatterns, and then each instance is processed to identify each independent test subpattern for the circuit design. Similar types of independent test subpatterns are merged into a circuit design test pattern, such that at least two of the independent test subpatterns associated with the circuit design occupy shared test cycles within the circuit design test pattern.

Abstract: Exemplary embodiments of the present disclosure relate to a clock distribution network for a scan design, which may include, for example, a clock signal network(s), and a plurality of partitioned clock signal networks coupled to the clock signal network(s) through a controlling logic(s); where the controlling logic(s) may be configured to stagger a clock signal from the clock signal network(s), and where each of the partitioned clock signal networks may be connected to a group of flip-flops. A first partitioned clock signal network of the partitioned clock signal networks may be connected to a first group of flip-flops and a second partitioned clock signal network of the partitioned clock signal networks may be connected to a second group of flip-flops, and where the first group of flip-flops may be different than the second group of flip-flops. The controlling logic(s) may include a shift register(s).

Abstract: Methods and computer-readable media for testing integrated circuit designs implement a physically efficient scan by optimally balancing and connecting scan segments in a 2-dimensional compression chain architecture. A compression architecture that provides an optimal and balanced configuration of scan segments in 2D compression grids to not only decrease test time, but also to maximize compression efficiency and limit wiring congestion for IC designs that contain complex scan segments facilitates efficient scanning of data by bisecting the elements into balanced partitions of the same target scan length. A segment padding algorithm, followed by a bisecting algorithm and ultimately an element swapping algorithm may be applied to optimally balance and connect scan segments in 2-D compression chains, optimizing an efficient compression architecture which minimizes scan testing resources and time.

Abstract: A test circuit includes a plurality of codec logic elements arranged in a plurality of annular rings on an integrated circuit, each codec logic element configured to provide test bits to one or more respective scan chain and receive test result bits from the one or more respective scan chain. The test circuit further includes a decompressor logic arranged along at least one annular ring of the plurality of annular rings on the integrated circuit, the decompressor logic configured to provide test bits to at least one codec logic element in each annular ring. The test circuit also includes a compressor logic arranged transversely with respect to the plurality of annular rings on the integrated circuit, the compressor logic configured to receive test result bits from at least one of the plurality of codec logic elements.

Abstract: Systems, methods, media, and other such embodiments described herein relate to insertion of test points in circuit design and associated test coverage for a circuit design. One embodiment involves a circuit design with a plurality of circuit elements and a plurality of clock gating logic elements. A first node coupled to a first circuit element is selected for insertion of a test point circuit element. Elements of the design are identified that contribute to a data state of the first node, and clock elements for these identified design elements are traced. An ungated clock input node from this trace is selected, and the clock input from this node is connected to the test point circuit element. The circuit design is then updated with this connection. In various embodiments when multiple ungated clock input nodes are identified by the trace, additional criteria are used to select among the ungated clock input nodes.

Abstract: Systems and methods disclosed herein provide for an integrated circuit partitioned into a plurality of regions of a two-dimensional grid, wherein each region of the grid corresponds to similarly located scan flops. The systems and methods also provide for enabling clock gates to scan flops in some regions of the integrated circuit and disabling clock gates to other regions in order to better manage power dissipation during ATPG. Specifically, toggle disabling templates are applied during ATPG in order to enable clock gates in certain regions of the two-dimensional grid.

Abstract: A system and methods to verify a correctness of data formatted according to an IEEE P1687 (IJTAG) standard, in connection with migration of test patterns from an instrument level to a top level of an integrated circuit design. Data describing an integrated circuit at the instrument level and at the top level is read from Instrument Connectivity Language (ICL) files, Procedural Description Language (PDL) files, and hardware description language (HDL) files. The methods include at least one of verifying structural descriptions of the integrated circuit in the ICL files and verifying an ability to use chip level inputs to access instruments in the integrated circuit. The verification procedure is performed prior to a simulation in which a migrated test pattern is applied to the integrated circuit.

Abstract: Embodiments relate to methodologies for applying multibit cell merging to functional shift registers, thereby saving area, reducing scan-wirelength, saving power and reducing wiring congestion in integrated circuit designs. In embodiments, during synthesis, shift registers in a design are identified. In these and other embodiments, in identified shift registers, functional shift register flip-flops are merged into non-scan multi-bit flip-flops using a physically aware approach.

Abstract: Systems disclosed herein provide for efficient top-level compactors for systems on a chip (SoCs) with multiple identical cores. Embodiments of the systems provide for compactors with a time-skewed assignment configuration, compactors with a space-skewed assignment configuration, compactors with time/space-skewed assignment configuration, and compactors that can selectively switch between the time/space-skewed assignment configuration and a symmetric assignment configuration.

Abstract: According to certain aspects, the present embodiments relate to optimizing core wrappers in an integrated circuit to facilitate core-based testing of the integrated circuit. In some embodiments, an integrated circuit design flow is adjusted so as to increase the use of shared wrapper cells in inserted core wrappers, and to reduce the use of dedicated wrapper cells in such core wrappers, thereby improving timing and other integrated circuit design features. In these and other embodiments, the increased use of shared wrapper cells is performed even in the presence of shift registers in the integrated circuit design.

Abstract: Systems and methods for a sequential decompressor which builds equations predictably provide a first-in, first out (“FIFO”) shift register which is fed by a first XOR decompressor and provides outputs to a second XOR decompressor.

Abstract: Systems and methods efficiently bring additional variables into a Pseudo-Random Pattern Generator (“PRPG”) in the early cycles of an automatic test pattern generation (“ATPG”) process without utilizing any additional hardware or control pins. Overscanning (e.g., scanning longer than the length of the longest channel) for some additional cycles brings in enough variables into the PRPG. Data corresponding to earlier cycles of the ATPG process is removed.

Abstract: Systems and methods disclosed herein provide for efficiently loading mask data to the mask register bits from the decompression network outputs of an ATPG system. The systems and methods also provide an elastic interface utilized between a tester and a decompressor network (e.g., sequential and combinational decompressors) in order to expand the number of input variables utilized during the loading of the mask data to the mask register bits.

Abstract: Systems and methods disclosed herein provide for generating extra variables for an ATPG system utilizing compressed test patterns in the event an ATPG process is presented with faults requiring a higher number of care-bits than can be supported efficiently by the current hardware. The systems and methods provide for a multi-stage decompressor network system with an embedded serializer-deserializer. The systems and methods use a XOR decompressor in a first stage and a serializer-deserializer in conjunction with a second XOR decompressor in a second stage.

Abstract: Methods and apparatus for decompressing test data using XOR trees for application to scan chains of a design for test (DFT) integrated circuit in a physically efficient construction are disclosed. Moreover, methods and apparatus for compressing test response data from scan chains in a DFT integrated circuit in a physically efficient construction are disclosed. The XOR tree decompression method may comprise splitting signals at each node of the XOR trees according to distribution logic implemented by a set of XOR gates. The XOR tree compression method may comprise combining signals at each node of the XOR trees according to combination logic implemented by a set of XOR gates.

Abstract: A CoDec in a design for test integrated circuit. In embodiments described herein, portions of the CoDec are distributed over the area of the IC. In particular, both the compressor and the decompressor may be distributed over the IC. To this end, XOR gates are located locally to the scan chains over the area of the chip to reduce wire length back to the input/output test pins. The compressor and decompressor may be distributed in a 2-dimensional grid. The compressor may XOR each scan chain in two different directions such that a fault may be resolved back to a specific region of the IC.