G01R31/31813

Systems and methods to detect cell-internal defects

A method of identifying cell-internal defects: obtaining a circuit design of an integrated circuit, the circuit design including netlists of one or more cells coupled to one another; identifying the netlist corresponding to one of the one or more cells; injecting a defect to one of a plurality of circuit elements and one or more interconnects of the cell; retrieving a first current waveform at a location of the cell where the defect is injected by applying excitations to inputs of the cell; retrieving, without the defect injected, a second current waveform at the location of the cell by applying the same excitations to the inputs of the cell; and selectively annotating, based on the first current waveform and the second current waveform, an input/output table of the cell with the defect.

Test System for Memory Card
20220074986 · 2022-03-10 ·

A test system for a memory card includes a first circuit board. One side of the first circuit board is provided with a plurality of contact groups spaced apart from each other along a row direction. Another side of the first circuit board is provided with slots disposed along the row direction. The test system further includes a second circuit board. The second circuit board is provided with a test circuit, and is inserted into the slot along a direction perpendicular to the first circuit board. The second circuit board provides a test signal to the contact groups.

Software defined LFSR for LOC delay testing low-power test compression
11156662 · 2021-10-26 · ·

A software-defined linear feedback shift register (SLFSR) implements a low-power test compression for launch-on-capture (LOC). Each bit of an extra register controls a stage of the SLFSR. A control vector is shifted into the extra register to indicate whether a primitive polynomial contains the stage of the non-zero bit. Therefore, SLFSR can configure any primitive polynomials with different degrees by loading different control vectors without any hardware overhead. A low-power test compression method and design for testability (DFT) architecture provide LOC transition fault testing by using seed encoding scheme, low-power test application procedure and a software-defined linear-feedback shift-register (SLFSR) architecture. The seed encoding scheme generates seeds for all test pairs by selecting a primitive polynomial that encodes all test pairs of a compact test set.

Flexible isometric decompressor architecture for test compression

A system for testing a circuit comprises scan chains, a controller, and hold-toggle circuitry. The hold-toggle circuitry is configured to allow, according to a control signal generated by the controller, some scan chains in the scan chains to operate in a full-toggle mode and some other scan chains in the scan chains to operate in a hold-toggle mode when a test pattern is being shifted into the scan chains. The control signal also contains information of a hold-toggle pattern for the scan chains operating in the hold-toggle mode. The hold-toggle pattern repeats multiple times when the test pattern is being shifted into the scan chains.

Display in a graphical format of test results generated using scenario models

A method for testing a system-on-a-chip (SoC) is described. The method includes parsing a file to determine functions to be performed components of the SoC. The method further includes receiving a desired output of the SoC and generating a test scenario model based on the desired output of the SoC. The test scenario model includes a plurality of module representations of the functions and includes one or more connections between two of the module representations. The desired output acts as a performance constraint for the test scenario model. The test scenario model further includes an input of the SoC that is generated based on the desired output, the module representations, and the one or more connections. The test scenario model includes a path from the input via the module representations and the connections to the desired output.

Testing SoC with portable scenario models and at different levels

A method for testing a system-on-a-chip (SoC) is described. The method includes parsing a file to determine functions to be performed components of the SoC. The method further includes receiving a desired output of the SoC and generating a test scenario model based on the desired output of the SoC. The test scenario model includes a plurality of module representations of the functions and includes one or more connections between two of the module representations. The desired output acts as a performance constraint for the test scenario model. The test scenario model further includes an input of the SoC that is generated based on the desired output, the module representations, and the one or more connections. The test scenario model includes a path from the input via the module representations and the connections to the desired output.

Empirical LBIST latch switching and state probability determination

Examples described herein provide a computer-implemented method that includes initiating a logic built-in self-test (LBIST) of a device under test (DUT). The method further includes performing latch state counting using a multiple input signature register (MISR) of the DUT, the performing responsive to the MISR being in a counter mode. The method further includes performing a latch transition counting of latches of the DUT using the MISR of the DUT and a storage latch, the performing responsive to the MISR being in the counter mode. The method further includes performing a latch count comparison by comparing an output of the MISR responsive to the MISR being in the counter mode to an output of a count compare register, the output of the count compare register representing a desired MISR state.

EMPIRICAL LBIST LATCH SWITCHING AND STATE PROBABILITY DETERMINATION
20210270898 · 2021-09-02 ·

Examples described herein provide a computer-implemented method that includes initiating a logic built-in self-test (LBIST) of a device under test (DUT). The method further includes performing latch state counting using a multiple input signature register (MISR) of the DUT, the performing responsive to the MISR being in a counter mode. The method further includes performing a latch transition counting of latches of the DUT using the MISR of the DUT and a storage latch, the performing responsive to the MISR being in the counter mode. The method further includes performing a latch count comparison by comparing an output of the MISR responsive to the MISR being in the counter mode to an output of a count compare register, the output of the count compare register representing a desired MISR state.

Trajectory-Optimized Test Pattern Generation for Built-In Self-Test

A circuit comprises: a bit-flipping signal generation device comprising a storage device and configured to generate a bit-flipping signal based on bit-flipping location information, the storage device configured to store the bit-flipping location information for a first number of bits, the bit-flipping location information obtained through a fault simulation process; a pseudo random test pattern generator configured to generate test patterns based on the bit-flipping signal, the pseudo random test pattern generator comprising a register configured to be a linear finite state machine, the register comprising storage elements and bit-flipping devices, each of the bit-flipping devices coupled to one of the storage elements; and scan chains configured to receive the test patterns, wherein the bit-flipping signal causes one of the bit-flipping devices to invert a bit of the register each time a second number of test patterns is being generated by the pseudo random test pattern generator during a test.

Digital-to-analog converter waveform generator

Techniques for testing circuits, such as converter circuits, such as digital-to-analog converter circuits (DACs), are described. A digital signal processor (DSP) can generate a waveform, such as sine wave, and apply the sine wave to the circuit under test, e.g., a DAC. The DAC can generate an output and the DSP can regenerate the waveform and determine an accuracy of the DAC such as to determine whether the DAC meets one or more specified criteria. In some example implementations, the tests can be performed using variable voltage amplitude segments.