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: 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: 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: 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: 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 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: Systems and methods disclosed herein provide for utilizing extra variables in the decompression equation set of an ATPG process for test patterns requiring an excess number of care bits than can be supported efficiently by the current hardware. An elastic interface is utilized between a tester and a decompressor network (e.g., sequential and combinational decompressors) in order to expand the test pattern length and/or the number of input variables. The systems and methods also provide care bits in early scan cycles of the ATPG process for sequential decompressors starting from a fixed state.

Abstract: Methods and computer-readable media for effecting physically efficient scans of integrated circuit designs may include selecting a two-dimensional grid size for exposure to the method, the two-dimensional grid having a size that includes a first side length, a second side length, and a number of flops. The method is performed to select a two-dimensional grid size that maximizes compression efficiency and limit wiring congestion on the IC. In one aspect, the method may be performed on each region of the grid that maintains one of a respective first side length and a respective second side length greater than one, including selecting a larger side, determining if the larger side is odd or even, and dividing the grid along the larger side into two regions each having a proportion of the flops. The scans of the resulting regions are efficient, and consequently facilitate integrated circuit design and subsequent manufacture.

Abstract: Methods, systems, and integrated circuits for decompressing a set of scan input data in a Design for Test (DFT) application, in which implementation may include determining a number of scan inputs to applied circuit from automated test equipment (ATE). Based on the number of scan inputs, another aspect of implementation may involve generating a 2-dimensional grid on the integrated circuit (IC). Another implementation aspect may involve decompressing the scan inputs from the ATE according to decompression logic that is sequentially distributed such that the grid can locally apply the last stage of the decompression logic. In accordance with aspects of the method, the physical structure of an IC decompression logic is more accessible to individual scan chains and reduces congestion on board the IC.