Abstract: A scan clock modifier, a method of providing a variable scan clock, an IC including a scan clock modifier and a library including a cell of a scan clock modifier. In one embodiment, the scan clock modifier includes: (1) logic circuitry configured to provide at least one selected clock signal based on a test scan clock signal and a first clock control signal, both of the test scan clock signal and the first clock control signal received from test equipment and (2) comparison logic configured to provide a scan clock signal based on the at least one selected clock signal and at least one other clock control signal received from the test equipment, wherein the first and the at least one other clock control signals are different clock control signals.

Abstract: A scan clock modifier, a method of providing a variable scan clock, an IC including a scan clock modifier and a library including a cell of a scan clock modifier. In one embodiment, the scan clock modifier includes: (1) logic circuitry configured to provide at least one selected clock signal based on a test scan clock signal and a first clock control signal, both of the test scan clock signal and the first clock control signal received from test equipment and (2) comparison logic configured to provide a scan clock signal based on the at least one selected clock signal and at least one other clock control signal received from the test equipment, wherein the first and the at least one other clock control signals are different clock control signals.

Abstract: A method for implementing test generation for systematic scan reconfiguration in an integrated circuit is presented. The method may comprise: defining at least one set of detectable faults; setting an SAS decoder configuration, the SAS decoder configuration including a don't-care bit; generating an ATPG pattern; and applying the ATPG pattern to one or more scan chain segments having a segment address associated with the SAS decoder configuration.

Abstract: The present invention is directed to a system and method for quality improvement by identifying test patterns for DFT logic faults and functional logic faults. The identified test patterns may be selectively utilized for pruning of patterns or DPM estimation. Functional faults and DFT faults may be identified from detected TDF faults. The functional faults are faults on a logic which was present in a pre-test insertion net list. Remaining faults are the DFT faults. A set of test patterns for DFT faults may be utilized as the first target for the pattern truncation which will reduce the amount of test patterns to be tested. A set of test patterns for functional may be utilized for improving the TDF coverage.

Abstract: The present invention is directed to a system and method for improving transition delay test coverage through use of enhanced flip flops (ES flip-flops) for a broadside test approach. Each ES flip-flop includes a two port flip-flop including a first flip-flop and a second flip-flop. A separate control input (ESM) which is not time critical is used to select a multiplexer of the second flip-flop. Thus, the ES flip-flops do not require a fast signal switching between launch and test response capture or an extra clock signal. Various enhanced scan modes may be selected via a combination of SEN and ESM. Moreover, only a heuristically selected subset of scan flip-flops may be replaced with the ES flip-flops so as to minimize the length of a scan chain as well as the logic area overhead. The present invention provides high TDF coverage under the broadside testing.

Abstract: The present invention is directed to a system and method for improving transition delay fault coverage through use of augmented flip-flops (TL flops) for a broadside test approach. The TL flops use the same clock for scan and functional operation. Thus, the TL flops do not require a fast signal switching between launch and test response capture. Each of the TL flops includes additional multiplexer in front of a standard scan flop and a transition enable (TEN) signal. Moreover, only a heuristically selected subset of scan flip-flops is replaced with the TL flops and only one additional MUX per selected scan flip-flop may contribute an area overhead. Consequently, the overall chip area overhead may be minimal. The present invention may be suitable for being implemented with currently available third party ATPG.

Abstract: The present invention is directed to a system and method for improving transition delay test coverage through use of enhanced flip flops (ES flip-flops) for a broadside test approach. Each ES flip-flop includes a two port flip-flop including a first flip-flop and a second flip-flop. A separate control input (ESM) which is not time critical is used to select a multiplexer of the second flip-flop. Thus, the ES flip-flops do not require a fast signal switching between launch and test response capture or an extra clock signal. Various enhanced scan modes may be selected via a combination of SEN and ESM. Moreover, only a heuristically selected subset of scan flip-flops may be replaced with the ES flip-flops so as to minimize the length of a scan chain as well as the logic area overhead. The present invention provides high TDF coverage under the broadside testing.

Abstract: The present invention is directed to a system and method for quality improvement by identifying test patterns for DFT logic faults and functional logic faults. The identified test patterns may be selectively utilized for pruning of patterns or DPM estimation. Functional faults and DFT faults may be identified from detected TDF faults. The functional faults are faults on a logic which was present in a pre-test insertion net list. Remaining faults are the DFT faults. A set of test patterns for DFT faults may be utilized as the first target for the pattern truncation which will reduce the amount of test patterns to be tested. A set of test patterns for functional may be utilized for improving the TDF coverage.

Abstract: The present invention is directed to a system and method for improving transition delay fault coverage through use of augmented flip-flops (TL flops) for a broadside test approach. The TL flops use the same clock for scan and functional operation. Thus, the TL flops do not require a fast signal switching between launch and test response capture. Each of the TL flops includes additional multiplexer in front of a standard scan flop and a transition enable (TEN) signal. Moreover, only a heuristically selected subset of scan flip-flops is replaced with the TL flops and only one additional MUX per selected scan flip-flop may contribute an area overhead. Consequently, the overall chip area overhead may be minimal. The present invention may be suitable for being implemented with currently available third party ATPG.

Abstract: Methods for implementing test generation and test application for systematic scan reconfiguration in an integrated circuit. All detectable faults of the integrated circuit are added to a set F. A SAS decoder configuration is selected to start with. ATPG patterns are generated for the faults in the set F for the selected decoder configuration. When F=Ø, a set of patterns Pi is reported for each decoder configuration i?C, where C is a set of selected decoder configurations.

Abstract: A method of scan chain integrity testing for an integrated circuit design includes steps of: (a) receiving as input an integrated circuit design; (b) generating a partial shift test bench for the integrated circuit design wherein the partial shift test bench includes scan chains stitched together into shift registers and a scan block; (c) parallel loading the scan chains with a set of test vectors from the scan block with an offset of N bits wherein N is a number greater than one and less than the maximum length of the scan chains; (d) shifting the last N bits of the test vectors into the scan chains with N scan clock pulses; (e) comparing outputs of the scan chains with expected values in the scan block to produce a scan chain integrity test result; and (f) generating as output the scan chain integrity test result.

Abstract: A method of grouping cells in an integrated circuit design includes steps of: (a) receiving as input a representation of an integrated circuit design; (b) initializing a corresponding list of cells for a common signal domain in the integrated circuit design; (c) selecting a cell belonging to a common signal domain that is not included in a corresponding list of cells for a common signal domain; (d) tracing a net from an input port of the selected cell to a signal driver and inserting the selected cell in the corresponding list of cells for the common signal domain associated with the signal driver; and (e) tracing the net to an input port of each cell connected to the signal driver and inserting each cell traced from the net in the corresponding list of cells for the common signal domain associated with the signal driver.

Abstract: A system and method identifies Iddq test vectors to be used in IDDQ testing of large CMOS circuits. This is achieved through intelligent preprocessing techniques. By monitoring only those nodes in the circuit that may be responsible for leakage current in the steady state, the size of the simulation results file is drastically reduced. The reduced simulation results file makes simulation a viable solution for IDDQ vector identification.

Abstract: A reduced netlist representing only partial netlist information for a logic block such as an ASIC embedded core is generated, such that proprietary information contained within the netlist can be kept confidential. The core is conceptually divided into a first section that can be completely tested using only a serial scan port, and a second section that can be tested in isolation from the first section using both primary inputs to the core as well as scan inputs. Netlist information for the first section is removed from the netlist, and the customer is supplied with serial scan test vectors that test the first section. Additionally, a multiplexing circuit selects either a serial scan chain for the entire logic block, or a scan chain that does not include scan cells within the first section of the logic bloc.