Abstract: An integrated circuit is disclosed that contains both a PMU and another processing portion, such as a baseband. Because of the limited pins devoted to the PMU, the PMU receives most of its signals through the other processing portion of the integrated circuit. Thus, in order to protect the PMU, the integrated circuit isolates the PMU portion from receiving different signals from the other processing portion until after certain conditions are satisfied. In addition, the integrated circuit includes a GPIO pin bank in the other processing portion that can be freely configured so as to allow for testing of the PMU.

Abstract: An integrated circuit is disclosed that contains both a PMU and another processing portion, such as a baseband. Because of the limited pins devoted to the PMU, the PMU receives most of its signals through the other processing portion of the integrated circuit, Thus, in order to protect the PMU, the integrated circuit isolates the PMU portion from receiving different signals from the other processing portion until after certain conditions are satisfied. In addition, the integrated circuit includes a GPIO pin bank in the other processing portion that can be freely configured so as to allow for testing of the PMU.

Abstract: A system, method, and apparatus for controlling tri-state drivers are presented herein. During scan testing, a decoder controls the tri-state drivers and prevents more than one tri-state driver from driving a shared resource, regardless of the test patterns shifted into the scan chain. During functional mode, the tri-state drivers are driven by functional enables.

Abstract: Various example embodiments are disclosed. According to one example embodiment, an integrated circuit may include a mode block, a plurality of data blocks, and a reset node. The mode block may be configured to output a test mode signal, a scan mode signal, and a trigger signal based on a received data input. The plurality of data blocks may each include registers configured to store data, each of the plurality of data blocks being configured to write over at least some of the data stored in their respective registers in response to receiving a write-over instruction. The reset node may be configured to reset the registers based on receiving either a first reset input or a second reset input. The integrated circuit may be configured to enter a test mode, enter a scan mode, and exit the test mode.

Abstract: Various example embodiments are disclosed. According to one example embodiment, an integrated circuit may include a mode block, a plurality of data blocks, and a reset node. The mode block may be configured to output a test mode signal, a scan mode signal, and a trigger signal based on a received data input. The plurality of data blocks may each include registers configured to store data, each of the plurality of data blocks being configured to write over at least some of the data stored in their respective registers in response to receiving a write-over instruction. The reset node may be configured to reset the registers based on receiving either a first reset input or a second reset input. The integrated circuit may be configured to enter a test mode, enter a scan mode, and exit the test mode.

Abstract: The present invention is directed to a method for debugging scan testing failures of integrated circuits. The method includes identifying good and bad scan paths among a set of scan paths. A scan path is bad if it is not producing any output. A scan path is good if it is producing a correct output. A clock set is generated for each scan path. The clock set includes all clock elements whose outputs impact the scan path. A union of the scan path clock sets for the bad scan paths is created. Good clock elements are removed from the union. A clock element is presumed to be good if it is associated with a good scan path. Clock elements remaining within the union of clock sets for the bad scan paths are analyzed to determine the source of errors. In one embodiment, multiple input clock elements in all bad scan paths are analyzed first, followed by analysis of single input clock elements in all bad scan paths and followed by analysis of any other clock elements in any of the bad scan paths.

Abstract: A method and system are disclosed for testing for double shift errors in at least one scan chain of flip-flops during a simulation of the design of a digital integrated circuit chip. At the start of the simulation, outputs of each flip-flop in the scan chain are initialized to a same known symbol (e.g., ‘X’). The flip-flops in the scan chain are clocked to shift binary digital symbols (zeros and ones) into the first flip-flop and through the successive flip-flops in the scan chain. During the shifting and clocking process, successive, contiguous pairs of flip-flop outputs are compared, one pair after each clock cycle. A double shift error is declared between the first flip-flop in the pair and the second flip-flop in the pair if the output symbols of the pair are the same.

Abstract: The present invention is directed to systems and method of controlling clock signals during scan testing integrated circuits. The methods and systems provide efficient at-speed scan testing while minimizing the external pins on an integrated circuit dedicated to scan testing clock sources. A clock control circuit is disclosed that includes a scan test control module for permitting a clock signal to be transmitted and a scan test clock decision module for determining whether a clock signal should be permitted to be transmitted. An integrated circuit is disclosed that includes a set of clock control circuits. Embodiments of a scan test control module are provided that can process decoder inputs, ATPG inputs or both. A method is provided that can be used, for example, by an ATPG tool to efficiently provided at-speed scan testing while minimizing external pins dedicated to scan testing clock sources.

Abstract: Herein described are at least a method and a system to perform scan testing of an integrated circuit chip using one or more internal and external clock sources. In a representative embodiment, the method comprises receiving at least one external clock signal and three control signals generated by an off-chip clock source, generating at least one internal clock signal from an on-chip clock source, and using the at least one external clock signal and the at least one internal clock signal by a logic circuitry to generate one or more scan test clocks to perform scan testing of one or more corresponding clock domains. In a representative embodiment, the system comprises at least one on-chip clock source and first and second circuitries for generating a scan test clock for a clock domain.

Abstract: Herein described are at least a method and a system to perform scan testing of an integrated circuit chip. The integrated circuit chip is scan tested using only a single scan clock. The single scan clock is provided through a single pin on the integrated circuit chip. In a representative embodiment, the method comprises inputting a single scan clock, first shifting data into one or more flip-flops of one or more scan chains by clocking the data into one or more scan in (SI) inputs of the one or more flip-flops using the single scan clock, selectively clocking flip-flops of a clock domain, and second shifting data from said one or more flip-flops of said one or more scan chains. In a representative embodiment, the system comprises one or more clock domains and one or more clock domain scan test modules.

Abstract: A method and apparatus are described for testing at least one critical data path in a design of a digital integrated circuit chip during a simulation of the design. A dedicated memory-bypass-enable signal is provided to a memory-bypass-logic circuit of the design during test modes of the simulation. Data content of a memory circuit within the critical data path is protected, using the dedicated memory-bypass-enable signal, during part of a path-delay test mode of the simulation. The memory circuit is also bypassed using the memory-bypass-enable signal during a memory-bypass test mode of the simulation.

Abstract: A method and system are disclosed, in a simulation of a design of a digital integrated circuit chip, to limit a number of scan test clocks and chip ports used for testing the chip. Clock domains are identified within the design of the chip that are independent of each other. The independent clock domains are grouped together, within said chip design, to form clock domain groups. A timing analysis is performed on the design of the chip by clocking the clock domain groups each with an independent scan test clock. The scan test clocks originate externally to the design and by-pass, within the chip design, the corresponding internal clocks. Capture mode violations are recorded from the timing analysis and are used to go back and form new clock domain groups, thereby repeating the method until no capture mode violations are generated.

Abstract: The present invention is directed to a method for debugging scan testing failures of integrated circuits. The method includes identifying a bad scan path among a set of scan paths and segmenting the bad scan path into two segments. Once the bad scan path is segmented into two segments, scan tests are run to determine whether the source of errors is near the segment point. If the number of errors generated is below a threshold, the specific location of errors can be identified by tracing the errors either manually or automatically through an automated testing unit. If the source of errors is not near the segment point, the segment point is shifted based on an analysis of the errors on the good and bad scan paths. Additional scan tests are then run and the method repeated until the location of the source of errors is found.

Abstract: A semiconductor device includes a JTAG boundary scan compliant testing architecture built into the semiconductor device, where the semiconductor device has a number of input points and output points. The JTAG boundary scan compliant testing architecture includes a TAP controller capable of receiving input test data, a test mode-select, and a test clock. In one embodiment, a full JTAG disable interface is utilized whereby the JTAG boundary scan compliant testing architecture allows an authorized user to prevent an unauthorized user from storing data into or reading data from input boundary scan registers and from reading data from output boundary scan registers. In another embodiment, a partial JTAG disable interface is utilized whereby an authorized user can prevent an unauthorized user from storing data into a pre-designated input boundary scan register, or from reading data from a pre-designated output boundary scan register.

Abstract: The present invention is directed to circuits and methods to efficiently conduct scan testing of integrated circuits in which first level packaging is varied to provide different versions of the integrated circuit. An integrated circuit is provided that includes at least one bond pad test circuit. The bond pad test circuit is coupled between a bond pad and functional components within an integrated circuit. In one embodiment, the bond pad test circuit includes a multiplexer and a D flip-flop in which the D input of the flip-flop is coupled to a bond pad. In another embodiment, the bond pad test circuit includes a multiplexer and a D flip-flop in which the D input of the flip-flop is coupled to the output of the multiplexer. A method for scan testing using an integrated circuit with a bond pad test circuit is also provided.

Abstract: Circuits and a method to enhance scan testing by controlling clock pulses that are provided to flip-flops within an integrated circuit are provided. An integrated circuit is provided that includes a scan testing clock control circuit for flip-flops. The scan testing clock control circuit enables control of a clock input signal to one or more flip-flops within the integrated circuit. In one embodiment, a scan testing clock control circuit can be used to ensure that a flip-flop receives a clock input signal during scan testing. In one embodiment the scan testing clock control circuit includes a latch, and an AND gate. A method for scan testing using a scan testing clock control circuit for flip-flops is also provided.

Abstract: A method and apparatus are disclosed for easily reconfiguring a scan chain test of a subset of scan blocks within a digital integrated circuit chip. To mitigate timing violations in the scan test of scan chains, alternative embodiments to implement a transfer of scan data to a next scan block are implemented.

Abstract: Circuits and methods to enhance scan testing by controlling clock pulses that are provided to memory devices within an integrated circuit are provided. An integrated circuit is provided that includes a scan testing clock control circuit and a memory bypass enable contact point. The scan testing clock control circuit enables control of a clock input signal to one or more memory devices within the integrated circuit. In one embodiment the scan testing clock control circuit includes a latch, and two AND gates. A scan test mode input and a memory bypass enable input are used to determine whether the memory will be permitted to receive a clock signal. Methods for scan testing using a scan testing clock control circuit are also provided.

Abstract: A method and system are disclosed for balancing a plurality of flip-flops across a number of global scan chains in a design of a digital integrated circuit chip. The design of the chip is organized into a number of discrete blocks such that each of the discrete blocks comprises a plurality of flip-flops. Within each discrete block, the plurality of flip-flops is connected to form a number of sub-chains of flip-flops. The sub-chains are then connected, within and across the discrete blocks, to generate a number of global scan chains such that the resultant number of flip-flops in each global scan chain is substantially the same.

Abstract: The present invention is directed to systems and method of controlling clock signals during scan testing integrated circuits. The methods and systems provide efficient at-speed scan testing while minimizing the external pins on an integrated circuit dedicated to scan testing clock sources. A clock control circuit is disclosed that includes a scan test control module for permitting a clock signal to be transmitted and a scan test clock decision module for determining whether a clock signal should be permitted to be transmitted. An integrated circuit is disclosed that includes a set of clock control circuits. Embodiments of a scan test control module are provided that can process decoder inputs, ATPG inputs or both. A method is provided that can be used, for example, by an ATPG tool to efficiently provided at-speed scan testing while minimizing external pins dedicated to scan testing clock sources.