Abstract: A circuit arrangement may include a scan test input stage having a test input for receiving a test signal, wherein the scan test input stage can be switched in high-impedance state; a data input stage having a data input for receiving a data signal, wherein the data input stage can be switched in high-impedance state. The circuit arrangement may further include a latch coupled to at least one output of the scan test input stage and to at least one output of the data input stage; and a drive circuit, which is configured to generate a pulsed clock signal for the data input stage and a signal for driving the scan test input stage.

Abstract: Programmable logic device integrated circuits with differential communications circuitry are provided in which the differential communications circuitry is used to support programming, testing, and user mode operations. Programming operations may be performed on a programmable logic device integrated circuit by receiving configuration data with the differential communications circuitry and storing the received configuration data in nonvolatile memory. The nonvolatile memory may be located in an external integrated circuit such as a configuration device or may be part of the programmable logic device integrated circuit. The stored configuration data may be loaded into configuration memory in the programmable logic device to program the device to perform a desired custom logic function. The differential communications circuitry may be used to handle boundary scan tests and programmable scan chain tests. During user mode operations the differential communications circuitry carries user data traffic.

Abstract: A device test architecture and interface is provided to enable efficient testing embedded cores within devices. The test architecture interfaces to standard IEEE 1500 core test wrappers and provides high test data bandwidth to the wrappers from an external tester. The test architecture includes compare circuits that allow for comparison of test response data to be performed within the device. The test architecture further includes a memory for storing the results of the test response comparisons. The test architecture includes a programmable test controller to allow for various test control operations by simply inputting an instruction to the programmable test controller from the external tester. The test architecture includes a selector circuit for selecting a core for testing. Additional features and embodiments of the device test architectures are also disclosed.

Abstract: The invention includes an apparatuses and associated methods for controlling dynamic modification of a testing scan path using a control scan path. In one embodiment, an apparatus includes a testing scan path and a control scan path. The testing scan path includes testing components and at least one hierarchy-enabling component. In one embodiment, the control scan path includes at least one control component coupled to the at least one hierarchy-enabling component for controlling dynamic modification of the testing scan path. In one embodiment, the control scan path includes the at least one hierarchy-enabling component, wherein the at least one hierarchy-enabling component is adapted for dynamically modifying the testing scan path using the control scan path. The dynamic modification of the testing scan path may include modifying a hierarchy of the testing scan path, such as selecting or deselecting one or more hierarchical levels of the testing scan path.

Abstract: This disclosure describes a reduced pin bus that can be used on integrated circuits or embedded cores within integrated circuits. The bus may be used for serial access to circuits where the availability of pins on ICs or terminals on cores is limited. The bus may be used for a variety of serial communication operations such as, but not limited to, serial communication related test, emulation, debug, and/or trace operations of an IC or core design. Other aspects of the disclosure include the use of reduced pin buses for emulation, debug, and trace operations and for functional operations.

Abstract: A technique for reducing the overhead of daisy chain test mode in divide-and-conquer testing using intermediate test modes that do not span all cores or all flip-flops in the core. The partial residual test mode spans across a subset of the cores and allows to bound the number of cores that a full residual test mode may span across. The interaction of the cores among one another at the top-level is analyzed and the minimum number of flip-flops in a core that must participate in a intermediate test mode is selected. Algorithms are devised to analyze the interactions among the cores and build data structures which are used for identifying intermediate test modes. Using a reconfigurable scan segment architecture, intermediate test modes are implemented that are designed to work with all known test compression solutions.

Abstract: Methods and apparatuses for synthesizing and/or implementing an augmented multimode compactor are described. An integrated circuit has circuitry that compacts test response data from scan chains in the integrated circuit under test. In many cases groups of the scan chains are coupled to output registers, such that a same group of scan chains is coupled to sequential elements of different output registers; and the same group is a subset of the scan chains including two or more scan chains. Various computer-implemented methods divide scan chains among at least groups and partitions. The groups disallow sharing a common scan chain from the scan chains, within a particular partition. At least one common scan chain is shared between the groups of different partitions.

Abstract: The present invention provides a microelectronic device with a circuit core and a boundary scan test interface sharing a number of pre-selected pins. In the mode of a boundary scan test, the boundary scan test interface manipulates the input and output of the test signal through the shared pins. Pins necessary for the microelectronic device are therefore reduced.

Abstract: A system is described having a JTAG diagnostic unit and a serial wire diagnostic unit. A watcher unit is connected to a data connection shared between the diagnostic units. Special patterns detected upon the shared data connection serve to switch between diagnostic modes with respective ones of the diagnostic units becoming active.

Abstract: The present invention provides a new hardware description language for chip-level JTAG testing. This new hardware description language, referred to as New BSDL (NSDL), enables testing resources of a system-on-chip to be described, thereby enabling the system-on-chip to be described in a manner that facilitates testing of the system-on-chip. The present invention provides a bottom-up approach to describing a system-on-chip. The present invention supports algorithmic descriptions of each of the components of the system-on-chip, and supports an algorithmic description of interconnections between the components of the system-on-chip, thereby enabling generation of an algorithmic description of the entire system-on-chip or portions of the system-on-chip. The present invention supports parallel access to one or more system-on-chip devices, including methods for describing and using parallel access for testing.

Abstract: A testing circuit has scan chain segments (62,64,60) defined between parallel inputs (wpi[0] . . . wpi[N?1]) and respective parallel outputs (wpo[0] . . . wpo[N?1]). The scan chain segments comprise a bank (62) of cells of a shift register circuit, a core scan chain portion (62), a first bypass path around the core scan chain portion (62) and a second bypass path around the bank (60) of cells of the shift register circuit. This architecture enables loading of data in parallel into the core scan chain, or into the shift register (WBR). In addition, each scan chain segment also has a series latching element (80), and this provides additional testing capability. In particular, the shifting of data between the latching elements (80) can be used to test the bypass paths while the internal or external mode testing is being carried out. This testing can thus be part of a single ATPG procedure.

Abstract: This invention transforms a circuit design at an asynchronous clock boundary using a flow involving register grouping, logic modification and level shifter and isolation cell insertion. The level shifter and isolation cell inserted are tested for proper location. The transformed circuit design is suitable for power consumption control by independent control of separate voltage domains.

Abstract: A pipelined scan compression method and apparatus for reducing test data volume and test application time in a scan-based integrated circuit without reducing the speed of the scan chain operation in scan-test mode or self-test mode. The scan-based integrated circuit contains one or more scan chains, each scan chain comprising one or more scan cells coupled in series. The method and apparatus includes a decompressor comprising one or more shift registers, a combinational logic network, and an optional scan connector. The decompressor decompresses a compressed scan pattern on its compressed scan inputs and drives the generated decompressed scan pattern at the output of the decompressor to the scan data inputs of the scan-based integrated circuit. Any input constraints imposed by said combinational logic network are incorporated into an automatic test pattern generation (ATPG) program for generating the compressed scan pattern for one or more selected faults in one-step.

Abstract: [PROBLEMS] To provide a semiconductor integrated circuit by which what has been referred to as two-pattern test is made possible without greatly increasing an occupying area. [MEANS FOR SOLVING PROBLEMS] The semiconductor integrated circuit is provided with a plurality of flip-flop circuits and selectors corresponding to each flip-flop circuit. Each flip-flop circuit is provided with a master latch and a slave latch connected to the master latch. The selector is electrically connected with the master latch of the flip-flop circuit to which the selector corresponds, and is also connected with the master latch of the flip-flop circuit other than the one to which the selector corresponds.

Abstract: A method and apparatus for testing or diagnosing faults in a scan-based integrated circuit using a unified self-test and scan-test technique. The method and apparatus comprises using a unified test controller to ease prototype debug and production test. The unified test controller further comprises using a capture clock generator and a plurality of domain clock generators each embedded in a clock domain to perform self-test or scan-test. The capture clocks generated by the capture clock generator are used to guide at-speed or reduced-speed self-test (or scan-test) within each clock domain. The frequency of these capture clocks can be totally unrelated to those of system clocks controlling the clock domains. This unified approach allows designers to test or diagnose stuck-type and non-stuck-type faults with a low-cost DFT (design-for-test) tester or a low-cost DFT debugger. A computer-aided design (CAD) method is further developed to realize the method and synthesize the apparatus.

Abstract: An integrated circuit (IC) arrangement (10) comprises an integrated circuit (100) having a digital circuit portion (120) with a plurality of digital outputs (122), each of the outputs being arranged to provide a test result in a test mode of the integrated circuit (100). The arrangement (10) further comprises space compaction logic (140) comprising a space compaction network (160) having a plurality of compaction domains (162), each domain being arranged to compact a plurality of test results into a further test result, and a spreading network (150) coupled between the plurality of digital outputs (122, 210) and the space compaction network (160), the spreading network being arranged to duplicate each test result from the digital outputs (122,210) to a number of compaction domains (162).

Abstract: Various apparatuses, methods and systems for dual JTAG controllers with shared pins disclosed herein. For example, some embodiments provide a boundary scan apparatus having a first boundary scan circuit with a first plurality of control inputs, a second boundary scan circuit with a second plurality of control inputs, and a plurality of boundary scan control signals connected to the first plurality of control inputs on the first boundary scan circuit and to the second plurality of control inputs on the second boundary scan circuit. At least two of the plurality of boundary scan control signals are connected between the first boundary scan circuit and the second boundary scan circuit in a crossover fashion.

Abstract: A shift register circuit is provided for storing instruction data for the testing of an integrated circuit core. The shift register circuit comprises a plurality of stages, each stage comprising a serial input (si) and a serial output (so) and a parallel output (wir_output) comprising one terminal of a parallel output of the shift register circuit. A first shift register storage element (32) is for storing a signal received from the serial input (si) and providing it to the serial output (so) in a scan chain mode of operation. A second parallel register storage element (38) is for storing a signal from the first shift register storage element (32) and providing it to the parallel output (wir_output) in an update mode of operation. The stage further comprises a feedback path (40) for providing an inverted version of the parallel output (wir_output) to the first shift register storage element (32) in a test mode of operation.

Abstract: A method and apparatus for testing an integrated circuit core or circuitry external to an integrated circuit core using a testing circuit passes a test vector from a parallel input of the testing circuit along a shift register circuit. The shift register circuit is configured to bypass one or more cores not being tested and to provide the test vector to a core scan chain of the core being tested. The bypassed cores are configured such that the associated shift register circuit portion is driven to a hold mode in which storage elements of the shift register circuit portion have their outputs coupled to their inputs. This method provides holding of the shift register stages when a core is bypassed and in a test mode, and this means the shift register stages are less prone to errors resulting from changes in clock signals applied to the shift register stages.

Abstract: The circuit and method providing dynamic scan chain partitioning delivers peak power reduction by dynamically partitioning scan chains into multiple groups, wherein transitions are equally distributed among these multiple groups. For each test pattern, a particular partitioning that leads to the even partitioning of the transitions is computed by analyzing the transition distribution of the pattern. The scan chain partitioning is formulated using an Integer Linear Programming (ILP) and an efficient greedy heuristic. The computed information is loaded into the reconfigurable scan chain partitioning hardware during the capture window. The partitioning hardware is composed of controllable clock gating logic, which is reconfigured on a per pattern basis, wherein the reconfiguration is effected by only utilizing the existing scan channels. The reconfigurability delivers a solution that is test set independent.

Abstract: A TAP linking module (21, 51) permits plural TAPs (TAPs 1-4) to be controlled and accessed from a test bus (13) via a single TAP interface (20).

Abstract: A test controller implemented in an integrated circuit (IC) with partitioned scan chains provides enhanced control in performing scan tests. According to an aspect, a test controller can selectively control scan-in, scan-out and capture phases of scan tests for different scan chains of the IC to be independent. The number of pins required to interface the test controller with an external tester is less than the number of partitions that the test controller can support. According to another aspect, an IC includes a register corresponding to each partition to support transition fault (or LOS) testing. According to another aspect, an IC with partitioned scan chains includes serial to parallel and parallel to serial converters, thereby minimizing the external pins required to support scan tests.

Abstract: A method for performing a logical built-in self-test of an integrated circuit is disclosed. The method includes performing a flush and scan test to determine whether the scan chains function correctly. If one of the scan chains does not function correctly, the logical built-in self-test is terminated. If each of the scan chains functions correctly, a structural test of the design-for-test logic supporting LBIST is performed to determine whether the LBIST design-for-test logic functions correctly. If the LBIST design-for-test logic does not function correctly, the logical built-in self-test is terminated. If the LBIST design-for-test logic functions correctly, a level sensitive scan design test of the functional combinational logic is performed using the logic supporting LBIST design-for-test to determine if the integrated circuit functions correctly.

Abstract: Methods and apparatuses for synthesizing and/or implementing an augmented multimode compactor are described.

Abstract: The circuit for boosting encoding capabilities of test stimulus decompressors is utilized in conjunction with a stimulus decompressor. The circuit, called align-encode is inserted between the decompressor and internal. The scan chains feed into a response compactor. The align-encode circuit is used to judiciously manipulate care bit distribution. Re-configurability of the align-encode circuit allows for this manipulation via delay cells with the align-encode circuit, whose length can be adjusted on a per scan chain per test pattern basis by loading the align-encode circuit with proper control data. Based on the stimulus decompressor characteristics, the scan chains are delayed in such a way that an unencodable pattern becomes encodable when using the align-encode circuit.

Abstract: A system comprises a circuit analysis module configured to analyze a device under test (DUT), the DUT comprising a plurality of latches coupled together in a scan chain. The circuit analysis module analyzes a DUT for sub-circuits within the DUT and identifies a logical description of identified sub-circuits. A don't-care analysis module couples to the circuit analysis module identifies absolute don't-care latches associated with the identified sub-circuits. A sub-circuit exception module couples to the circuit analysis module and selects weighted input values for an identified sub-circuit, based on the identified absolute don't-care latches and the logical description of the identified sub-circuit. The sub-circuit exception module stores the selected weighted input values for the sub-circuit and associates the selected weighted input values with the logical description.

Abstract: A system comprises a circuit analysis module configured to analyze a device under test (DUT), the DUT comprising a plurality of latches coupled together in a scan chain. A don't-care analysis module identifies absolute don't-care latches within the DUT, assigns a weighted value to the bit positions of identified don't-care latches, and identifies absolute don't-care bits within a general test pattern. The circuit analysis module replaces identified absolute don't-care bits in the general test pattern according to the weighted value of the associated bit position, generating a weighted test pattern. A test vector module generates a test vector based on the weighted test pattern and an input module applies the test vector to the DUT.

Abstract: A device test architecture and a reduced device test interface are provided to enable efficient testing of embedded cores and other circuits within devices. The reduced device test interface is achieved using a double data rate (DDR) signaling technique between the tester and the device. The DDR test interface allows the tester to interface to test circuits within the device, such as IEEE 1500 and/or IEEE 1149.1 test circuits, to provide high test data bandwidth to the test circuits using a minimum of test interface signals. The test architecture includes compare circuits that allow for comparison of test response data to be performed within the device. The test architecture further includes a memory for storing the results of the test response comparisons. The test architecture includes a programmable test controller to allow for various test control operations by simply inputting an instruction to the programmable test controller from the external tester.

Abstract: The present disclosure describes novel methods and apparatuses for directly accessing JTAG Tap domains that exist in a scan path of many serially connected JTAG Tap domains. Direct scan access to a selected Tap domain by a JTAG controller is achieved using auxiliary digital or analog terminals associated with the Tap domain and connected to the JTAG controller. During direct scan access, the auxiliary digital or analog terminals serve as serial data input and serial data output paths between the selected Tap domain and the JTAG controller.

Abstract: A scan technique using linear matrix to drive scan chains is used, along with an ATPG, to constraint scan test vectors to be generated through the linear matrix. The linear matrix scan technique reduces the test application time and the amount of test vector data by several orders of magnitude over conventional techniques, without reducing fault coverage.

Abstract: In a semiconductor device including an N-line M-stage shift register circuit operated at high speed of, for example, several hundreds MHz. Input circuits input a common test pattern to each of pairs of shift registers in, for example, two lines out of the N lines. A plurality of outputs of the pairs of shift registers in the two lines are compared in comparators, and the comparison results are output. The N-line M-stage shift register circuit and the comparators are operated in synchronization with a clock signal at several hundreds MHz. Hence, even when the circuit scale (area) of the N-line M-stage shift register circuit is increased to involve apparent wiring delay, a defect in the shift register circuit can be detected at an actual speed.

Abstract: A Scan-BIST architecture is adapted into a low power Scan-BIST architecture. A generator 102, compactor 106, and controller 110 remain the same as in the known art. The changes between the known art Scan-BIST architecture and the low power Scan-BIST architecture involve modification of the known scan path into scan path 502, to insert scan paths A 506, B 508 and C 510, and the insertion of an adaptor circuit 504 in the control path 114 between controller 110 and scan path 502.

Abstract: A computer is programmed to prepare a computer program for simulating operation of an integrated circuit (IC) chip, in order to test scan circuitry therein. The computer is programmed to trace a path through combinational logic in a design of the IC chip, starting from an output port of a first scan cell and ending in an input port of a second scan cell. If the first and second scan cells receive a common scan enable signal, then the computer generates at least a portion of the computer program, i.e. software to perform simulation of propagating a signal through the path conditionally, for example when the common scan enable signal is inactive and alternatively to skip performing simulation when the common scan enable signal is active. The computer stores the portion of the computer program in memory, for use with other such portions of the computer program.

Abstract: A method, system and computer program product for testing the Design-For-Testability/Design-For-Diagnostics (DFT/DFD) and supporting BIST functions of a custom microcode array. Upon completion of the LSSD Flush and Scan tests, the ABIST program is applied to target the logic associated direct current (DC) and alternating current (AC) faults of ABIST array Design-For-Testability/Design-For-Diagnostics DFT/DFD functions that support the microcode array. A LSSD test of the DFT functional combinational logic is performed by applying generated LSSD deterministic test patterns targeting the ABIST design-for-test faults to determine if the DFT supporting the microcode array is functioning correctly. Additional tests may be terminated upon resulting failure of the applied ABIST DFT circuitry surrounding the arrays.

Abstract: Scan architectures are commonly used to test digital circuitry in integrated circuits. The present invention describes a method of adapting conventional scan architectures into a low power scan architecture. The low power scan architecture maintains the test time of conventional scan architectures, while requiring significantly less operational power than conventional scan architectures. The low power scan architecture is advantageous to IC/die manufacturers since it allows a larger number of circuits (such as DSP or CPU core circuits) embedded in an IC/die to be tested in parallel without consuming too much power within the IC/die. Since the low power scan architecture reduces test power consumption, it is possible to simultaneously test more die on a wafer than previously possible using conventional scan architectures. This allows wafer test times to be reduced which reduces the manufacturing cost of each die on the wafer.

Abstract: The present disclosure describes a novel method and apparatus of using the JTAG TAP's TMS and TCK terminals as a general purpose serial Input/Output (I/O) bus. According to the present disclosure, the TAP's TMS terminal is used as a clock signal and the TCK terminal is used as a bidirectional data signal to allow serial communication to occur between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC.

Abstract: A test architecture and method of testing are disclosed to allow multiple scan controllers, which control different scan chain designs in multiple logic blocks, to share a test access mechanism. During test mode, the test architecture is configured to decouple clock sources of the test access mechanism, the scan controllers and the scan chains.

Abstract: A system on chip (SOC) may include function blocks, and a scan chain in each of the function blocks, the scan chains being adapted to conduct scan test operations in sync with a respective one of a plurality of clock signals having a different phase relative to each other, wherein during an isolation mode, the scan chains test combination circuits of the function blocks, and during an interface mode, the scan chains of adjacent ones of the function blocks test combination circuits between the adjacent ones of the function blocks.

Abstract: A method for testing at least two arithmetic units installed in a control unit includes: loading of first test data for testing a first arithmetic unit; saving the loaded first test data in a second memory unit of a second arithmetic unit; switching the first arithmetic unit to a test mode, in which a first scan chain of the first arithmetic unit is accessible; reading the first test data from the second memory unit; shifting the first test data which have been read through the first scan chain of the first arithmetic unit switched to the test mode for providing test result data for the first arithmetic unit; checking the provided test result data for plausibility for providing a test result for the first arithmetic unit.

Abstract: Disclosed herein are exemplary embodiments of a so-called “X-press” test response compactor. Certain embodiments of the disclosed compactor comprise an overdrive section and scan chain selection logic. Certain embodiments of the disclosed technology offer compaction ratios on the order of 1000×. Exemplary embodiments of the disclosed compactor can maintain about the same coverage and about the same diagnostic resolution as that of conventional scan-based test scenarios. Some embodiments of a scan chain selection scheme can significantly reduce or entirely eliminate unknown states occurring in test responses that enter the compactor. Also disclosed herein are embodiments of on-chip comparator circuits and methods for generating control circuitry for masking selection circuits.

Abstract: A test architecture accesses IP core test wrappers within an IC using a Link Instruction Register (LIR). An IEEE P1500 standard is in development for providing test access to these individual cores via a test structure called a wrapper. The wrapper resides at the boundary of the core and provides a way to test the core and the interconnections between cores.-The test architecture enables each of the plural wrappers in the IC, including wrappers in cores embedded within other cores, with separate enable signals.

Abstract: Method and apparatus for operating for operating an Institute of Electrical and Electronics Engineers (IEEE) Standard 1149.1 compliant Joint Test Action Group (JTAG) Test Access Port (TAP) controller are disclosed. An example apparatus includes write logic that is configured to operationally interface with a TAP controller and a processor. The write logic is further configured to receive, from the processor, data for initializing the apparatus and operating the TAP controller, convert at least a portion of the data from a parallel format to a serial format and communicate the converted data to the TAP controller.

Abstract: Memory compiler engineers often focus on the efficient implementation of the largest possible memory configurations for each memory type. The overhead of test and control circuitry within memory implementations is usually amortized across a large number of storage bits. Unfortunately, test structures generally do not scale down with decreasing memory sizes, creating a large area penalty for a design with numerous small memories. One solution is a scannable register file (SRF) architecture using scannable latch bit-cells laid out using a standard cell layout/power template. All sub-cells can be placed in standard cell rows and utilize standard cell power straps. Non-SRF standard cells can be abutted on all sides, placement keep-out regions are not needed. Metal utilization is usually limited to first three metallization layers. The bit-cell is much larger than standard compiled memory bit cells, but has no overhead beyond address decode, word-line drivers, and read-write data latches.

Abstract: An integrated circuit or circuit board includes functional circuitry and a scan path. The scan path includes a test data input lead, a test data output lead, a multiplexer, and scan cells. A dedicated scan cell has a functional data output separate from a test data output. Shared scan cells each have a combined output for functional data and test data. The shared scan cells are coupled in series. The test data input of the first shared scan cell is connected to the test data output of the dedicated scan cell. The combined output of one shared scan cell is coupled to the test data input lead of another shared scan cell. The multiplexer has an input coupled to the test data output, an input connected to the combined output lead of the last shared scan cell in the series, and an output connected in the scan path.

Abstract: A structural design-for-test for diagnosing broken scan chain defects of long non-scannable register chains (GPTR) The GPTR and the system for testing and diagnosing the broken LSSD scan-only chains rapidly localize defects to the failing Shift Register Latch (SRL) pair. The GPTR modifies the latches used in the GPTR scan chain to standard LSSD L1/L2 master-slave SRL type latch pairs; connects all the system ports of the L1 latches to the Shift Register Input (SRI) and clocked by the system C1-clk while the L1 scan port is clocked by the A-clk and L2 scan port is clocked only by the B-clk. The L1 latches are connected to at least one multiplexer having a first output connected to an input of each odd SRL, and a second output connected to an input port of each even SRL.

Abstract: Mechanisms for testing functional boundary logic at an asynchronous clock boundary of an integrated circuit device are provided. With these mechanisms, each clock domain has its own scan paths that do not cross domain boundaries. By eliminating the scanning across the boundaries, the requirement to have two clock grids in the asynchronously clocked domains may be eliminated. As a result, circuit area and design time with regard to the clock distribution design are reduced. In addition, removing the second clock grid, i.e. the high speed core or system clock, in the asynchronously clocked domains removes the requirement to have a multiplexing scheme for selection of clocking signals in the asynchronous domain. In addition to the above, the system and method provide boundary built-in-self-test logic for testing the functional crossing logic of boundaries between the clock domains in a functional mode of operation.

Abstract: A method and apparatus for providing ordered capture clocks to detect or locate faults within N clock domains and faults crossing any two clock domains in a scan-based integrated circuit or circuit assembly in self-test or scan-test mode, where N>1 and each domain has a plurality of scan cells. The method and apparatus will apply an ordered sequence of capture clocks to all scan cells within N clock domains where one or more capture clocks must contain one or more shift clock pulses during the capture operation. A computer-aided design (CAD) method is further developed to realize the method and synthesize the apparatus. In order to further improve the circuit's fault coverage, a CAD method and apparatus are further developed to minimize the memory usage and generate scan patterns for full-scan and feed-forward partial-scan designs containing transparent storage cells, asynchronous set/reset signals, tri-state busses, and low-power gated clocks.

Abstract: Testing of die on wafer is achieved by; (1) providing a tester with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuitry, (2) providing die on wafer with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuity, and (3) providing a connectivity mechanism between the bidirectional transceiver circuitry's of the tester and a selected group or all of the die on wafer for communication of the JTAG signals.

Abstract: Methods, apparatuses and articles for testing security of a mapping function—such as a Physically Unclonable Function (PUF)—of an integrated circuit (IC) are disclosed. In various embodiments, one or more tests may be performed. In various embodiments, the tests may include a predictability test, a collision test, a sensitivity test, a reverse-engineering test and an emulation test. In various embodiments, a test may determine a metric to indicate a level of security or vulnerability. In various embodiments, a test may include characterizing one or more delay elements and/or path segments of the mapping function. Other embodiments may be described and claimed.

Abstract: An approach for producing optimized integrated circuit designs that support sequential flow partial scan testing may be embedded within an integrated circuit electronic design device. Using the approach, an integrated circuit design may be analyzed to identify and remove scan-enabled memory elements, or scan elements, that are redundant. The redundant scan elements may be replaced with memory elements that do not support scan testing. Once the redundant scan elements are removed, the integrated circuit design my be optimized using automated techniques to reduce the area of the integrated circuit physical layout and to simplify/minimize routing connections between remaining features within the integrated circuit design. The described approach may achieve a reduced total area layout and complexity, an improved time/frequency response, and/or reduced power consumption and/or heat generation within the circuit design, without reducing the fault coverage achieve during testing.