Patent classifications
G01R31/318342
MULTI-CYCLE TEST GENERATION AND SOURCE-BASED SIMULATION
A system and method generates test patterns for simulating a circuit design. Generating the test patterns includes determining clock data of the circuit design. The clock data is determined by determining a first clock signal pair from clock signals, and determining a disturb cell based on the first clock signal pair. The disturb cell is electrically coupled to a first clock signal of the first clock signal pair, and to a second cell. The second cell is electrically coupled to a second clock signal of the first clock signal pair, and an input of the second cell is electrically coupled to an output of the disturb cell. A first test pattern is generated based on the clock data and is output to a memory to be used in simulating a circuit design.
Noise-compensated jitter measurement instrument and methods
A test and measurement device includes an input for receiving a test waveform from a Device Under Test (DUT), where the test waveform has a plurality of input level transitions, a selector structured to respectively and individually extract only those portions of the test waveform that match two or more predefined patterns of input level transitions of the test waveform, a noise compensator structured to individually determine and remove, for each of the extracted portions of the waveform, a component of a jitter measurement caused by random noise of the test and measurement device receiving the test waveform, a summer structured to produce a composite distribution of timing measurements with removed noise components from the extracted portions of the test waveform, and a jitter processor structured to determine a first noise-compensated jitter measurement of the DUT from the composite distribution. Methods of determining noise-compensated jitter measurements are also disclosed.
Signal toggling detection and correction circuit
The signal toggling detection and correction circuit includes a flip-flop, a checker circuit, and a fault monitoring circuit that includes a restoration circuit. Based on faults such as soft errors and unintended bit toggles in the flip-flop, a flop output signal toggles. A set of checker signals outputted by the checker circuit may toggle based on toggling of the flop output signal and a restoration signal of the restoration circuit. Based on the toggling of at least one checker signal, the fault monitoring circuit determines whether the flip-flop or the checker circuit is faulty. When the checker circuit is faulty, the fault monitoring circuit corrects the toggling of at least one checker signal. When the flip-flop is faulty, the fault monitoring circuit corrects the toggling of one of the toggled flop output signal or the restoration signal and further corrects the toggled checker signal.
Input data compression for machine learning-based chain diagnosis
Various aspects of the disclosed technology relate to machine learning-based chain diagnosis. Faults are injected into scan chains in a circuit design. Simulations are performed on the fault-injected circuit design to determine test response patterns in response to the test patterns which are captured by the scan chains. Observed failing bit patterns are determined by comparing the unloaded test response patterns with corresponding good-machine test response patterns. Bit-reduction is performed on the observed failing bit patterns to construct training samples. Using the training samples, machine-learning models for faulty scan cell identification are trained. The bit reduction comprises pattern-based bit compression for good scan chains or cycle-based bit compression for the good scan chains. The bit reduction may further comprise bit-filtering. The bit-filtering may comprises keeping only sensitive bits on faulty scan chains for the training samples construction.
Measurement system as well as method of providing statistical information
A measurement system includes a measurement module, a processing module, and a display. The measurement module is configured to conduct measurements on a device under test in a repetitive manner in order to obtain measurement results assigned to the repeated measurements. The processing module is configured to combine the measurement results obtained. The processing module is also configured to perform a statistical analysis in a live manner in order to calculate at least one of a live statistical significance parameter of the combined measurement results and a time duration required to obtain a certain statistical significance of the measurement results. The display is configured to display at least one of the live statistical significance parameter and the time duration. Further, a method of providing statistical information is described.
Automated waveform analysis using a parallel automated development system
A mixed signal testing system capable of testing differently configured units under test (UUT) includes a controller, a test station and an interface system that support multiple UUTs. The test station includes independent sets of channels configured to send signals to and receive signals from each UUT being tested and signal processing subsystems that direct stimulus signals to a respective set of channels and receive signals in response thereto. The signal processing subsystems enable simultaneous and independent directing of stimulus signals through the sets of channels to each UUT and reception of signals from each UUT in response to the stimulus signals. Received signals responsive to stimulus signals provided to a fully functional UUT (with and without induced faults) are used to assess presence or absence of faults in the UUT being tested which may be determined to include one or more faults or be fault-free, i.e., fully functional.
Fault rules files for testing an IC chip
A fault rules engine generates a plurality of fault rules files. Each of the fault rules files is associated with a respective cell type of a plurality of cell types in an integrated circuit (IC) design, and each fault rules file of the plurality of fault rules files can include data quantifying a nominal delay for a given two-cycle test pattern of a set of two-cycle test patterns and data quantifying a delta delay for the given two-cycle test pattern corresponding to a given candidate defect of a plurality of candidate defects for a given cell type in the IC design. An IC test engine generates cell-aware test patterns based on the plurality of fault rules files to test a fabricated IC chip that is based on the IC design for defects corresponding to a subset of the plurality of candidate defects characterized in the plurality of fault rules files.
Circuit division method for test pattern generation and circuit division device for test pattern generation
A circuit division method for test pattern generation in which a computer performs processes of: acquiring, for each of a plurality of blocks included in a target circuit for test pattern generation, a first feature amount regarding a size of each block and a second feature amount regarding a function of the block; classifying the plurality of blocks into a plurality of groups so that blocks for which the acquired first feature amount is within a first predetermined range and the acquired second feature amount is within a second predetermined range belong to an identical group; and assigning, for each of the classified groups, each of the blocks included in the group to one of a plurality of divided circuits of a division number based on a ratio of the number of blocks included in the group to the division number by which the plurality of blocks are divided.
Automatic test-pattern generation for memory-shadow-logic testing
An embodiment of a method for automated test pattern generation (ATPG), a system for ATPG, and a memory configured for ATPG. For example, an embodiment of a memory includes a first test memory cell, a data-storage memory cell, and a test circuit configured to enable the test cell and to disable the data-storage cell during a test mode.
Method to perform hardware safety analysis without fault simulation
A safety analysis method is based on a safety-specific design structural analysis and cone of influence (COI) that does not require fault simulation. The method for performing a safety analysis of an integrated circuit based on a safety-specific design structural analysis and cone of influence comprises generating with a processor a computed set of basic design elements by intersecting two transitive cones of influence, wherein a first cone of influence is a transitive fanin cone of influence starting from a TO element and a second cone of influence is a transitive fanout cone of influence starting from a FROM element.