Abstract: A clock generating circuit includes an input terminal, configured to receive a clock signal; an output terminal, configured to output an output signal; a gray counter circuit, coupled to the input terminal, and configured to divide the clock signal to produce a first output signal; and a shielding circuit, coupled to the input terminal, the gray counter circuit and the output terminal, and configured to shield a glitch in the first output signal to generate the output signal according to the clock signal.

Abstract: An integrated circuit includes a standard cell including a first output pin and a second output pin configured to each output the same output signal, a first routing path connected to the first output pin, and a second routing path connected to the second output pin. The first routing path includes a first cell group including at least one load cell, the second routing path includes a second cell group including at least one load cell, and the first routing path and the second routing path are electrically disconnected from each other outside the standard cell.

Abstract: A fuzzy scoreboard can compute, using a signature function, a first signature of an expected data stream associated with an input data stream that is being inputted to a design-under-test (DUT) for a datapath test. The first signature of the expected data stream can be stored without storing the expected data stream. The fuzzy scoreboard can also compute, using the same signature function, a second signature of an output data stream that is outputted from the DUT during the datapath test. The first signature can be compared with the second signature to determine whether there is a match. Storing the first signature of the expected data stream without storing the expected data stream can reduce the memory space consumed by the fuzzy scoreboard.

Abstract: According to an embodiment, a method for testing a triple-voting flop (TVF) is provided. The method includes providing a first and a second scan enable signal by a control circuit to, respectively, a first scan flip-flop and a third scan flip-flop of the TVF; receiving a third scan enable signal at the second scan flip-flop of the TVF; providing a scan input signal to the first scan flip-flop, the second scan flip-flop, and the third scan flip-flop; controlling the first scan enable signal, the second scan enable signal, and the third scan enable signal; receiving, at an output of the TVF, a scan output signal; and determining whether the TVF suffers from a fault based on the scan output signal and the controlling of the first scan enable signal, the second scan enable signal, and the third scan enable signal.

Abstract: Disclosed herein are embodiments related to a power efficient multi-bit storage system. In one configuration, the multi-bit storage system includes a first storage circuit, a second storage circuit, a prediction circuit, and a clock gating circuit. In one aspect, the first storage circuit updates a first output bit according to a first input bit, in response to a trigger signal, and the second storage circuit updates a second output bit according to a second input bit, in response to the trigger signal. In one aspect, the prediction circuit generates a trigger enable signal indicating whether at least one of the first output bit or the second output bit is predicted to change a state. In one aspect, the clock gating circuit generates the trigger signal based on the trigger enable signal.

Abstract: A disclosed technique includes clock gating a plurality of data elements of a first clock domain of a scan dump network; outputting data from a plurality of data elements of a second clock domain of the scan dump network; clock gating the plurality of data elements of the second clock domain; and outputting data from the plurality of data elements of the first clock domain.

Abstract: A vertical field effect transistor (VFET) cell implementing a VFET circuit over a plurality of gate grids includes: a 1st circuit including at least one VFET and provided over at least one gate grid; and a 2nd circuit including at least one VFET and provided over at least one gate grid formed on a left or right side of the 1st circuit, wherein a gate of the VFET of the 1st circuit is configured to share a gate signal or a source/drain signal of the VFET of the 2nd circuit, and the 1st circuit is an (X?1)-contacted poly pitch (CPP) circuit, which is (X?1) CPP wide, converted from an X-CPP circuit which is X CPP wide and performs a same logic function as the (X?1)-CPP circuit, X being an integer greater than 1.

Abstract: Methods and systems are provided for testing three-dimensional (3D) stacked dies of integrated circuits (ICs). The methods and systems receive, by test signal routing logic implemented on a first die, a first die test signal, the test signal routing logic operating in an elevate mode or turn mode. The methods and systems receive a second die test signal from a second die and route the first die test signal to an external device in the turn mode. The methods and systems route the second die test signal received from the second die to the external device in the elevate mode.

Abstract: This application provides decompression circuits. An example decompression circuit includes a plurality of sub-circuits. The sub-circuit includes a plurality of cellular automaton (CA) circuits and a phase shifter. Each of the plurality of CA circuits includes a first XOR circuit and a register. The first XOR circuit includes a first input end, a second input end, and an output end. A data input end of the register is coupled to the output end of the first XOR circuit. A data output end of the register is coupled to the first input end of the first XOR circuit and an input end of the phase shifter. The data output end of the register is further coupled to the second input end of the first XOR circuit in a different CA circuit. The phase shifter is configured to output a test signal.

Abstract: An output-amplifier-based reciprocal quantum logic (RQL) bias-level sensor is used to measure and/or calibrate bias parameters of AC and/or DC bias signals provided to RQL circuitry. The bias signals can include an output amplifier output bias current. The bias-level sensor includes a stack of DC SQUIDs that are supplied their inputs from outputs of respective Josephson transmission lines (JTLs) to which the SQUIDs are transformer-coupled. Staging relative strengths of the bias taps of the JTLs, or the critical currents of the Josephson junctions in the DC SQUIDs, allows an output voltage signal of the bias-level sensor to be indicative of whether a provided bias value is an improvement or optimization of the bias value when varied over a range. The outputs of two such bias-level sensors driven by I and Q clocks can be compared to adjust AC bias amplitudes of the clocks. Relative clock phase can be similarly adjusted.

Abstract: Circuits, systems, and methods are described herein for increasing a hold time of a master-slave flip-flop. A flip-flop includes circuitry configured to receive a scan input signal and generate a delayed scan input signal; a master latch configured to receive a data signal and the delayed scan input signal; and a slave latch coupled to the master latch, the master latch selectively providing one of the data signal or the delayed scan input signal to the slave latch based on a scan enable signal received by the master latch.

Abstract: A packaged integrated circuit (IC) chip that provides input/output (I/O) signal fail safe verification is disclosed. The packaged IC chip includes a first processing unit, a first control peripheral coupled to receive a first processed signal from the processing unit and to provide an output signal, and compare logic. The compare logic is coupled to receive the output signal and a comparison signal, to compare the output signal and the comparison signal, and to provide an error signal responsive to a difference between the output signal and the comparison signal.

Abstract: A configuration management system tracks the configuration of a managed computing environment in accordance with a configuration tracking policy. The configuration management system uses the tracking policy to map configuration information from the managed computing environment to a hierarchy of configuration items. Items may be included or excluded from the hierarchy based on relevance to the tracking policy and a predicted amount of dynamism. A signature of the hierarchy is generated. A change to the configuration environment is detected based on a change to the signature, and an action is performed in response to the detected change.

Abstract: A scan chain may be formed throughout an integrated circuit in which the scan chain is coupled to a set of pins via bi-directional input/output (I/O) buffers. A state machine may be provided to control the scan chain. Decoding logic may monitor states and transitions between states and generate pseudo static control signals in response to certain states and transition sequences in order to free up test pins for use as additional scan data I/O pins using a single JTAG IR. A test pattern may be received from an external tester using the set of I/O pins and buffers operating in parallel. The test pattern may then be provided to combinatorial logic circuitry coupled to the scan chain. A response pattern may be captured in the scan chain. The response pattern may then be provided to the external tester using the same set of I/O pins and buffers operating in parallel.

Abstract: A processing unit can include a performance monitor for monitoring the performance of the processing unit and associated sub-units. The performance monitor includes a logic analyzer, and implements a state machine via state machine data entries stored in a memory associated with the performance monitor. A state machine data entry includes output signals associated with state transitions. The output signals include a next state and a trigger to the logic analyzer. The performance monitor implements logic circuits that determine, based on input signals and the state machine data entries, the next state to transition and associated output signals. If a state transition includes a trigger to the logic analyzer, the trigger is transmitted to the logic analyzer. In response to the trigger, the logic analyzer assembles and samples input signals and stores the sampled input signals into the memory associated with the performance monitor, overwriting the state machine data entries.

Abstract: Herein are techniques that train regressor(s) to predict how effective would a machine learning model (MLM) be if trained with new hyperparameters and/or dataset. In an embodiment, for each training dataset, a computer derives, from the dataset, values for dataset metafeatures. The computer performs, for each hyperparameters configuration (HC) of a MLM, including landmark HCs: configuring the MLM based on the HC, training the MLM based on the dataset, and obtaining an empirical quality score that indicates how effective was said training the MLM when configured with the HC. A performance tuple is generated that contains: the HC, the values for the dataset metafeatures, the empirical quality score and, for each landmark configuration, the empirical quality score of the landmark configuration and/or the landmark configuration itself. Based on the performance tuples, a regressor is trained to predict an estimated quality score based on a given dataset and a given HC.

Abstract: A system includes a ring oscillator including an odd number of inverters arranged in a ring. The system also includes a time to digital converter including an odd number of flops, where each of the flops is coupled to an output of a different inverter. The system includes a level shifter coupled to the inverters and to the flops. The system also includes a Gray counter coupled to at least one of the flops. The system includes a decoder coupled to the time to digital converter. The system also includes a phase frequency detector coupled to the decoder.

Abstract: An integrated circuit device includes a plurality of cells or modules. Each respective one of the cells or modules consumes leakage power, and the amount of leakage power consumed by a respective one of the cells or modules varies depending on states of its inputs. Scan-chain circuitry is configured to propagate through the integrated circuit device, on entry of the integrated circuit device to a low-power mode, a scan-chain pattern created in advance, to apply, to each respective cell or module in the low-power mode, a set of inputs that results in a respective low-power state with reduced leakage power. Creating the scan chain pattern includes identifying respective ones of the cells or modules as having the highest leakage power consumption, and a respective combination of inputs to place each of those the cells or modules in a respective low-power state.

Abstract: A system includes a test access port (TAP) configured to provide internal joint test action group (IJTAG) access to one or more test data registry (TDR). The system further includes a plurality of hierarchical electronic components, wherein each hierarchical electronic component includes a de-asserted segment inserted bit (D-SIB) register, an asserted segment inserted bit (A-SIB) register, and a TDR associated with the D-SIB register. Each D-SIB register is configured to prevent access to its associated TDR when a reset signal is asserted and each A-SIB register is configured to provide access to its subsequent A-SIB register or D-SIB register coupled thereto when the reset signal is asserted.

Abstract: Disclosed is a transceiver which includes a logic circuit that generates parallel transmission data in response to a first test mode signal or a second test mode signal, a serializer that converts the parallel transmission data into serial transmission data, a driver that outputs the serial transmission data through transmission pads, an analog circuit that receives serial reception data through reception pads, a deserializer that converts the serial reception data into parallel reception data, a plurality of test switches switched in response to the first test mode signal, and a test circuit that is electrically connected to the analog circuit through the plurality of test switches and outputs serial post data corresponding to the serial transmission data to the analog circuit.

Abstract: A method is provided in the present disclosure. The method includes several operations: generating, by a processing unit, a mapping table associated with multiple scan chains and multiple shift cycles corresponding to multiple values stored in the scan chains in an integrated circuit; determining, based on the mapping table, at least one fail flip flop in the scan chains in response to the values outputted from the scan chains; and identifying at least one fault site corresponding to the at least one fail flip flop.

Abstract: Systems and methods disclosed include receiving defect data from a test of a semiconductor device comprising a circuit, the circuit comprising a cell, the cell comprising a first input, a second input and an output, and modeling a first plurality of cell defect modes of the cell with a first multiple input transition cell fault model (MTCFM), the cell defect modes associated with a first signal transition on the first input, and a second signal transition on the second input or the output. Systems and method further include correlating the first plurality of cell defect modes to the defect data to produce a probability of each of the first plurality of cell defect modes matching the defect data, and providing, to a user, an indication of each of at least one of the first plurality of cell defect modes having the probability exceeding a defect probability threshold.

Abstract: A data labeling method, apparatus and system are provided. The method includes: sampling a data source according to an evaluation task for the data source to obtain sampled data; generating a labeling task from the sampled data; sending the labeling task to a labeling device; and receiving a labeled result of the labeling task from the labeling device. As such, an automatic evaluation of data can be implemented by using the evaluation task, and evaluation efficiency is improved.

Abstract: 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.

Abstract: Disclosed are a circuit unit, a circuit module and an apparatus for data statistics. The circuit unit comprises a first register and a second register, and stores data received via a first input terminal in the first register in a case where a first control terminal receives a valid control signal, stores data received via a second input terminal in the second register in a case where a second control terminal receives a valid control signal, and increases the value of data stored in the second register by 1 in a case where a third control terminal receives a valid control signal. The circuit module comprises one or more such circuit units, and the apparatus comprises one or more such circuit modules. The circuit module or the apparatus may use smaller resource and smaller power consumption to complete data statistics.

Abstract: An integrated circuit comprises scan test circuitry, additional circuitry subject to testing utilizing the scan test circuitry, and control circuitry associated with the scan test circuitry. The scan test circuitry comprises a scan chain having a plurality of scan cells, and the associated control circuitry is coupled to at least a given one of a primary input of the integrated circuit and a primary output of the integrated circuit. The scan test circuitry is configurable by the control circuitry so as to permit testing of both an input functional path associated with the given one of the primary input and the primary output and an output functional path associated with the given one of the primary input and the primary output.

Abstract: A combo dynamic flop with scan flop circuit includes a flip-flop circuit, a scan control circuit, and an output buffer circuit. The flip-flop circuit includes a dynamic latch circuit and a static latch circuit. The dynamic latch circuit includes a dynamic latch storage node. The static latch circuit includes a static storage node driven by the dynamic latch. The scan control circuit includes a scan slave feed-forward circuit, a scan latch circuit, and a scan driver circuit driven by the scan feed-back circuit. The scan latch circuit includes a scan feed-back circuit, a scan storage node, and a scan feed-forward circuit driven from the static latch. The output buffer circuit includes a dynamic latch driver driven from the dynamic latch circuit and a static driver driven from the static latch circuit.

Abstract: A scan flip-flop circuit comprises a scan input sub-circuit and a selection sub-circuit. The scan input sub-circuit is configured to receive a scan input signal and a scan enable signal and, when the scan enable signal is activated, generate complementary scan input signals representing the scan input signal that are delayed relative to a transition of a clock input signal between two different logic levels. The selection sub-circuit is coupled to the scan input sub-circuit and configured to receive the complementary scan input signals and, based on the scan enable signal, output an inverted version of either the scan input signal or a data signal as a first selected input signal.

Abstract: Each register in each built-in self-test (BIST) controller contains a BIST controller-specific start count value that is different from at least one other BIST controller-specific start count. A test controller provides a start command simultaneously to all the BIST controllers. This causes each of the BIST controllers to simultaneously begin a countdown of the BIST controller-specific start count values, using a counter. Each of the BIST controllers starts a test procedure in a corresponding BIST domain when the countdown completes (in the corresponding BIST controller). Thus, the test procedure starts at different times in at least two of the BIST domains based on the difference of the BIST controller-specific start count values in the different registers. Further, during the test procedure, each stagger controller can stagger the start of each BIST engine within the corresponding BIST domain to which the stagger controller is connected.

Abstract: A test architecture for 3D ICs is provided in which Through-Silicon-Vias and die logic can be tested pre-bonding dies in the stack for the 3D ICs. Post-bond scan test architecture is reconfigured to be accessed during pre-bond testing through using stratigically placed MUXs and TSVs. By connecting post-bond architecture including scan flops and boundary registers to gated scan flops used in TSV testing, an internal chain of scan flops such as typically used in post-bond testing can be selectively connected to gated scan flops connected to one end of each TSV for pre-bond testing of the internal logic through the TSVs.

Abstract: Systems and methods for latches are presented. In one embodiment a system includes scan in propagation component, data propagation component, and control component. The scan in propagation component is operable to select between a scan in value and a recirculation value. The data propagation component is operable to select between a data value and results forwarded from the scan in propagation component, wherein results of the data propagation component are forwarded as the recirculation value to the scan in propagation component. The control component is operable to control an indication of a selection by the scan in propagation component and the data propagation component.

Abstract: The invention provides a boundary scan test interface circuit. The boundary scan test interface circuit includes N test input pads, a test interfacing module and M test output pads, wherein N and M are positive integers, and M is smaller than N. The test interfacing module is coupled to the test input pads. The test interfacing module having a plurality of logical gates, and each of input pins of each of the logical gates coupled to each of the test input pads. The test output pads are coupled to output pins of the logical gates in the test interfacing module.

Abstract: A processor includes a TCU TAP for access of a TCU for running functional tests and a DAP TAP for access of a debugger. A TAP selection module selects reversibly TAP access by default through the TCU TAP when the processor is a bare die, or by default through the DAP TAP when the processor is packaged, the selection of TAP access being reversible by the TCU. The processor also includes a fuse for irreversibly disabling the selection by the TAP selection module of the TAP access by default through the TCU TAP. Functional tests on bare dies are run with a TCU probing the dies through the TCU TAP by default. Packaged engineering samples can be supplied for debugging with the DAP TAP selected by default, but access possible for the TCU through the TCU TAP.

Abstract: Circuits and methods are provided for debugging an integrated circuit. An integrated circuit includes core circuitry, scan test circuitry, scan control circuitry, and debug control circuitry. The scan test circuitry includes scan chains with scan cells interspersed throughout the core circuitry. The scan control circuitry controls the scan test circuitry to scan test the core circuitry. The debug control circuitry utilizes the scan test circuitry and controls the scan control circuitry to debug failure conditions of the integrated circuit during normal use. The scan control circuitry applies a debug clock signal to a clock port of each scan cell of a given scan chain to store data values that are generated by the core circuitry into the scan cells. The scan control circuitry controls the scan test circuitry to scan shift out the stored data values generated by the core circuitry during the debug process.

Abstract: An integrated circuit comprises scan test circuitry and additional circuitry subject to testing utilizing the scan test circuitry. The scan test circuitry comprises a scan chain having a plurality of scan cells. The integrated circuit further comprises a clock distribution network configured to provide clock signals to respective portions of the integrated circuit. The clock distribution network comprises a clock tree having clock signal lines, and clock control elements arranged in respective selected ones of the clock signal lines of the clock tree, where the clock control elements are configured to separate at least one synchronous clock domain into multiple asynchronous clock domains during scan testing. The clock control elements may be configured to reduce a number of timing exceptions produced during scan testing relative to a number of timing exceptions that would otherwise be produced if scan testing were performed using the synchronous clock domain.

Abstract: A path-based crosstalk fault model is used in conjunction with a built-in self-test (BIST) and software capability for automatic test pattern generation. The solution allows for test patterns to be generated that maximize switching activity as well as inductive and capacitive crosstalk. The path based fault model targets the accumulative effect of crosstalk along a particular net (“victim” path), as compared with the discrete nets used in conventional fault models. The BIST solution allows for full controllability of the target paths and any associated aggressors. The BIST combined with automatic test pattern generation software enables defect detection and silicon validation of delay defects on long parallel nets.

Abstract: Systems and techniques for hot-plugging debugger capabilities are described. A described integrated circuit device includes a processor, a first pad interface, a detector configured to detect a clock signal via the first pad interface, one or more second pad interfaces, two or more components including a debug system that is communicatively coupled with the processor, a multiplexer communicatively coupled with the one or more second pad interfaces and the two or more components, and configured to selectively interconnect the one or more second pad interfaces with a selected component of the two or more components. The multiplexer can be configured to cause the debug system to be the selected component when the clock signal is detected via the first pad interface.

Abstract: Techniques and mechanisms for evaluating I/O buffer circuits. In an embodiment, test rounds are performed for a device including the I/O buffer circuits, each of the test rounds comprising a respective loop-back test for each of the I/O buffer circuits. Each of the test rounds corresponds to a different respective delay between a transmit clock signal and a receive clock signal. In another embodiment, a first test round indicates a failure condition for at least one I/O buffer circuit and a second test round indicates the failure condition for each of the I/O buffer circuits. Evaluation of the I/O buffer circuits determines whether the device satisfies a test condition, where the determining is based on a difference between the delay corresponding to the first test round and the delay corresponding to the second test round.

Abstract: A computer-implemented method for test case result processing includes receiving, by a test case result processing logic in a processor of a computer, a test result from a test case that executes on the computer; determining, by the test case result processing logic based on a result description file, whether a result description corresponding to the received result exists in the result description file; based on the result description corresponding to the received result existing in the result description file, determining an action description associated with the result description based on an action definition file; and executing an action corresponding to the determined action description.

Abstract: An integrated circuit includes an LBIST controller operative to run a test program on at least one selection of core logic of the integrated circuit to test the operability of the at least one selection of core logic. The integrated circuit also includes a monitoring logic structure operative to detect at least one type of operation executed for the test program from at least one particular control signal activated by the LBIST controller for controlling the at least one selection of core logic to execute the test program from among at least one control signal for controlling operations on the at least one selection of core logic.

Abstract: A system and method for efficiently debugging an integrated circuit with on-die hardware. A processor core includes an on-die debug state machine (DSM). The DSM includes multiple programmable storage elements for storing parameter values corresponding to multiple contexts. Each context is associated with a given one of multiple instruction sequences, such as at least threads and power-performance states. The DSM detects a sequence identifier (ID) and selects a context based on the sequence ID. The corresponding parameter values are used by transition conditions (triggers) and taken debug actions in a finite state machine (FSM) within the DSM. Each state and transition in the FSM is used by each one of the multiple contexts. The programmable DSM shares many resources, rather than replicating them, while being used for multiple sequences.

Abstract: A low power scan flip-flop cell includes a multiplexer, a master latch, a scan slave latch and a data slave latch. The master latch is connected to the multiplexer, and used for generating a first latch signal. The scan slave latch is connected to the master latch, and generates a scan output (SO) signal. The data slave latch is connected to the master latch, and generates a Q output depending on a scan enable (SE) input signal and the first latch signal. The Q output is maintained at a predetermined level during scan mode, which eliminates unnecessary switching of combinational logic connected to the scan flip-flop cell and thus reduces power consumption.

Abstract: A system for performing a scan test on an integrated circuit such as a System on a Chip (SoC) that may be packaged in different package types and with different features enabled includes a bypass-signal generator and a first scan-bypass circuit. The bypass-signal generator generates a first bypass signal based on chip package information. The first bypass signal indicates whether a first scan chain associated with a first non-common circuit block of the SoC is to be bypassed. The first scan chain is bypassed in response to the first bypass signal. By enabling partial scan testing based on package information, unintentional yield loss caused by a full scan test determining an SoC is faulty can be avoided.

Abstract: An integrated circuit comprises scan test circuitry and additional circuitry subject to testing utilizing the scan test circuitry. The scan test circuitry comprises at least one scan chain having scan cells. The scan test circuitry is configured to control at least a given one of the scan cells so as to prevent the scan cell from capturing a potentially non-deterministic value from a portion of the additional circuitry. The portion of the additional circuitry that provides the potentially non-deterministic value may comprise, for example, at least one of a mixed signal logic block and a memory block of the additional circuitry. The given scan cell may be controlled by configuring the scan cell such that it is unable to capture data in a scan capture mode of operation in which it would otherwise normally be able to capture data.

Abstract: A system for testing an error detection circuit includes a fault injection unit for operating the error detection circuit in a fault injection mode. A fault is inserted in either of a primary or a redundant processor. Output signals generated by the primary and redundant processors are compared and checked for a mismatch and the error detection circuit outputs a test signal based on the comparison result.

Abstract: Embodiments relate to systems and methods for defect detection and localization in semiconductor chips. In an embodiment, a plurality of registers is arranged in a semiconductor chip. The particular number of registers can vary according to a desired level of localization, and the plurality of registers are geometrically distributed such that defect detection and localization over the entire chip area or a desired chip area, such as a central active region, is achieved in embodiments. In operation, a defect detection and localization routine can be run in parallel with other normal chip functions during a power-up or other phase. In embodiments, the registers can be multi-functional in that they can be used for other operational functions of the chip when not used for defect detection and localization, and vice-versa. Embodiments thereby provide fast, localized defect detection.

Abstract: A method and apparatus for detecting clock glitches during at-speed testing of integrated circuits is disclosed. In one embodiment, an integrated circuit includes a scan chain having a number of scan elements coupled in a series configuration. Each of the scan elements is coupled to receive a clock signal that may be cycled during a test operation. A subset of the scan elements are arranged to form, along with other components, a counter. Test stimulus data shifted into the scan chain to perform a test may include an initial count value that is shifted into the scan elements of the counter. When the test is performed, the count value is updated responsive to cycling of the clock signal. The updated count value is shifted from the counter along with other test result data, and may be used to determine if the number of clock cycles received during the test.

Abstract: A method for detecting unstable signatures when testing a VLSI chip that includes adding to an LFSR one or more save and restore registers for storing an initial seed consisting of 0s and 1s; loading the initial seed into the one or more save and restoring LFSR registers upon reaching a predetermined number of test loops; performing a signature stability test by loading said initial seed to said LFSR, executing the predetermined number of BIST test loops, and comparing the resulting MISR signature for differences versus a previous signature stored in a MISR save and restore register.

Abstract: Methods and apparatus for testing Input/Output (I/O) boundary scan chains for Systems on a Chip (SoCs) having I/Os that are powered off by default. Some methods and apparatus include implementation of boundary scan chain bypass routing schemes that selectively route a boundary scan chain path around I/O interfaces and/or ports that are powered off by default. Other techniques include selectively power-on I/Os that are powered off by default in a manner that is independent of SoC facilities for controlling the power state of the I/Os during SoC runtime operations. Various schemes facilitate boundary scan testing in accordance with IEEE Std.-1149.1 methodology.

Abstract: Techniques related to remotely boundary scanning of an integrated circuit embedded in a target computing system are disclosed herein. In an example, a host computing system includes a first peripheral port and a second peripheral port. A port-to-port boundary scan assembly is to interface boundary scan data between the first and the second peripheral ports. Thereby the boundary scan data can be routed from the second peripheral bus to the target computing system via a network port at the host computing system.