Patent classifications
G01R31/318357
Automated assisted circuit validation
A method comprising categorizing nodes of a fabricated circuit as being priority nodes and nodes as being inferior nodes; evaluating a first priority node by automatically designating for verification the first priority node, and ascertaining whether a measured signal from the first priority node meets a pass-fail criterion for the first priority node; evaluating, when the measured signal from the first priority node meets the pass-fail criterion, a second priority node by automatically designating for verification the second priority node, and ascertaining whether a measured signal from the second priority node meets a pass-fail criterion for the second priority node; and evaluating, when the measured signal from the first priority node does not meet the pass-fail criterion, a first inferior node, by automatically designating for verification the first inferior node, and ascertaining whether a measured signal from the first inferior node meets a pass-fail criterion for the first inferior node.
METHOD AND SYSTEM FOR EFFICIENT TESTING OF DIGITAL INTEGRATED CIRCUITS
One embodiment provides a method and a system for generating test vectors for testing a computational system. During operation, the system obtains a design of the computational system, the design comprising an original system. The system generates a design of a fault-augmented system block by adding a plurality of fault-emulating subsystems to the original system; generates a design of an equivalence-checking system based on the original system and the fault-augmented system block; encodes the design of the equivalence-checking system into a logic formula, with variables within the logic formula comprising inputs and outputs of the original system and inputs and outputs of the fault-augmented system block; and solves the logic formula to obtain a test vector used for testing at least one fault in the computational system.
Systems and methods for configurable switches for verification IP
An emulator system and a method for emulating functionalities of an integrated circuit design are disclosed. In one aspect, the system includes a plurality of verification components each comprising circuitry configured to perform transactions with at least another verification component. The system can include a plurality of proxies, each executing on a processor and corresponding to a respective one of the verification components. The system can include a switch that is communicatively coupled with the proxies, the switch dynamically configurable to, in a first time duration, operate with a first subset of the proxies to enable a first transaction between a functional module of the design and a first verification component. The switch can be dynamically configurable to, in a second time duration, operate with a second subset of the proxies to enable a second transaction between the functional module and a second verification component.
Suspect resolution for scan chain defect diagnosis
This application discloses a computing system implementing an automatic test pattern generation tool to perform scan chain diagnosis-driven compaction setting. The computing system can perform fault simulation on scan chains in a circuit design describing an integrated circuit, which loads test patterns to the simulated scan chains and unloads test responses from the simulated scan chains. The computing system can determine locations of sensitive bits and locations of unknown bits in each of the scan chains based on the test responses from the simulated scan chains, and generate a configuration for a compactor in the integrated circuit based, at least in part, on the locations of the sensitive bits and the locations of the unknown bits in each of the scan chains, wherein the compactor is configured to compact test responses from the scan chains in the integrated circuit based on the configuration.
Emulation system supporting computation of four-state combinational functions
An emulation processor may be configured to support emulating unknown binary logic based on non-arbitrariness of the unknown binary logic. For example, an unknown binary logic signal may take the finite binary values of 0 and 1. The circuitry in the emulation processor is configured to generate and propagate outputs based on the interactions of known input binary signals with the unknown input binary signals having non-arbitrary states. The emulation processor may support the both combinational and sequential operations associated with the unknown binary logic.
Per-shift X-tolerant logic built-in self-test
A circuit is described that can include: a first register to store a first value that specifies a first subset of a set of scan chains, wherein the first subset of the set of scan chains includes scan cells that are desired to be masked; a second register to store a second value that specifies, in each shift cycle, a second subset of the set of scan chains, wherein the second subset of the set of scan chains includes scan cells that are desired to be masked; and a masking circuit to mask, in each shift cycle, scan cells in a third subset of the set of scan chains that is an intersection of the first subset of the set of scan chains and the second subset of the set of scan chains.
Timed transition cell-aware ATPG using fault rule files and SDF 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. Each fault rules file includes data quantifying a nominal delay for a given two-cycle test pattern 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 of a given cell type of the plurality of cell types in the IC design. An IC test engine extracts an input to output propagation delay for each cell instance from a standard delay format (SDF) file for the IC design and generates cell-aware test patterns for each cell instance of each cell type in the IC design based on the plurality of fault rules files and the extracted input to output propagation delays.
Systems and methods for non-invasive current estimation
A technique for non-invasively assessing current drawn by a device under test (DUT) by monitoring a supply voltage to the DUT. Frequency data for the DUT may be generated and used to form a current estimation model. First and second voltages are simultaneously measured using first and second test probes electrically connected to the DUT, while the first test probe is connected at a current source, and while the second test probe is connected at a DUT load that is configured to draw current from the current source. The current drawn by the DUT is then assessed by applying the current estimation model to the measured first and second voltages. In one case, the current drawn by the DUT is estimated without insertion of a circuit component into the DUT or extraction of a circuit conductor from the DUT.
SUSPECT RESOLUTION FOR SCAN CHAIN DEFECT DIAGNOSIS
This application discloses a computing system implementing an automatic test pattern generation tool to perform scan chain diagnosis-driven compaction setting. The computing system can perform fault simulation on scan chains in a circuit design describing an integrated circuit, which loads test patterns to the simulated scan chains and unloads test responses from the simulated scan chains. The computing system can determine locations of sensitive bits and locations of unknown bits in each of the scan chains based on the test responses from the simulated scan chains, and generate a configuration for a compactor in the integrated circuit based, at least in part, on the locations of the sensitive bits and the locations of the unknown bits in each of the scan chains, wherein the compactor is configured to compact test responses from the scan chains in the integrated circuit based on the configuration.
ELECTRONIC SIGNAL VERIFICATION USING A TRANSLATED SIMULATED WAVEFORM
A system for verifying signals in electronic circuits that includes a waveform translator and a test-and-measurement instrument. The waveform translator is configured to receive a simulated waveform for a node of a simulated prototype circuit and to translate the simulated waveform into a translated waveform. The test-and-measurement instrument is configured to obtain a measured waveform and to determine a deviation of the measured waveform from the simulated waveform using the translated waveform.