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 further comprises transition launch mode selection circuitry configured to provide independent selection between multiple transition launch modes for each of a plurality of clock domains of the integrated circuit. The multiple transition launch modes may include, for example, at least a launch-on-shift mode and a launch-on-capture mode. These transition launch modes provide different manners of launching a given signal transition via at least one of the scan cells in a corresponding one of the clock domains. The transition launch mode selection circuitry may be configured to generate from a common shift enable signal multiple independently controllable shift enable signals for respective ones of the clock domains of the integrated circuit.

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 plurality of scan chains each having a plurality of scan cells. The scan test circuitry further comprises control circuitry comprising first switching elements configured to control selective application of respective scan input signals to respective scan inputs of respective ones of the plurality of scan chains and second switching elements configured to control selective application of a shift enable signal to respective shift enable inputs of the respective ones of the plurality of scan chains. By appropriate control of the switching elements using test data register bits or other scan chain specific control signals, one or more debug modes can be supported by the scan test circuitry of the integrated circuit.

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 plurality of scan chains, including at least one wrapper cell scan chain arranged between first and second circuitry cores of the additional circuitry, with the wrapper cell scan chain comprising a plurality of wrapper cells and being configurable to operate as a serial shift register in a scan shift mode of operation. At least one of the wrapper cells of the wrapper cell scan chain comprises a flip-flop having a throughput data path that is part of a scan shift path of the wrapper cell scan chain and not part of a functional path between the first and second circuitry cores. In an HDD controller embodiment, the first and second circuitry cores may comprise respective read channel and additional cores of a system-on-chip.

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: 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 a plurality of scan cells, wherein the scan chain is separated into a plurality of scan segments with each such segment comprising a distinct subset of two or more of the plurality of scan cells. The scan test circuitry further comprises scan segment bypass circuitry configured to selectively bypass one or more of the scan segments in a scan shift mode of operation. The scan segment bypass circuitry may comprise a plurality of multiplexers and a scan segment bypass controller. The multiplexers are arranged within the scan chain and configured to allow respective ones of the scan segments to be bypassed responsive to respective bypass control signals generated by the scan segment bypass controller.

Abstract: Coding circuitry for difference-based data transformation in an illustrative embodiment comprises a difference-based encoder having a plurality of processing stages, with the difference-based encoder being configured to generate respective orders of difference from a sequence of data samples and to output encoded data determined based on at least a selected one of the orders of difference. The coding circuitry may be configured to implement lossless, linear compression of the sequence of data samples. The coding circuitry may additionally or alternatively comprise a difference-based decoder having a plurality of processing stages, with the difference-based decoder being configured to process encoded data comprising selected ones of a plurality of orders of difference and to reconstruct a sequence of data samples based on the selected orders of difference.

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: 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: An integrated circuit comprises a decoder having a plurality of select signal outputs, a multiplexer having a plurality of select signal inputs subject to a specified select signal constraint, and scan test circuitry. The scan test circuitry comprises at least one scan chain having a plurality of scan cells coupled between respective ones of the select signal outputs of the decoder and respective ones of the select signal inputs of the multiplexer. The scan test circuitry is configured to control at least a given one of the scan cells so as to prevent violation of the select signal constraint in conjunction with scan testing. The multiplexer may be, for example, a one-hot multiplexer for which the select signal constraint indicates that only one of the select signal inputs should receive a logic high select signal at a particular time.

Abstract: An integrated circuit comprises scan test circuitry and additional circuitry subject to testing utilizing the scan test circuitry. The scan test circuitry comprises transition control circuitry configured to detect transitions between binary logic levels in a scan test signal, and responsive to a number of detected transitions reaching a threshold, to limit further transitions associated with a remaining portion of the scan test signal. In an illustrative embodiment, the transition control circuitry limits further transitions associated with the remaining portion of the scan test signal by replacing at least part of the remaining portion of the scan test signal with a limited transition signal. The limited transition signal may be maintained at a constant binary logic level such that it has no transitions. By limiting the number of transitions associated with the scan test signal, the transition control circuitry serves to reduce integrated circuit power consumption during scan testing.

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 plurality of scan chains coupled to the additional circuitry, a scan capture clock generator configured to generate a scan capture clock signal having a controllable number of capture pulses, and a clock selection circuit configured to select between at least the scan capture clock signal and a scan shift clock signal for application to clock signal inputs of the scan chains. In one embodiment, the scan capture clock generator comprises a finite state machine, a plurality of capture clock pulse circuits each generating a capture clock pulse signal comprising a different number of capture clock pulses, and logic circuitry coupled to the finite state machine and having inputs adapted to receive the outputs of the capture clock pulse circuits.

Abstract: Coding circuitry comprises at least an encoder configured to encode an instruction address for transmission to a decoder. The encoder is operative to identify the instruction address as belonging to a particular one of a plurality of groups of instruction addresses associated with respective distinct program constructs, and to encode the instruction address based on the identified group. The decoder is operative to identify the encoded instruction address as belonging to the particular one of a plurality of groups of instruction addresses associated with respective distinct program constructs, and to decode the encoded instruction address based on the identified group. The coding circuitry may be implemented as part of an integrated circuit or other processing device that includes associated processor and memory elements. In such an arrangement, the processor may generate the instruction address for delivery over a bus to the memory.

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 further comprises scan delay defect bypass circuitry comprising multiplexers arranged within the scan chain. At least a given one of the multiplexers is configured to allow a corresponding one of the scan cells to be selectively bypassed in a scan shift configuration of the scan cells responsive to a delay defect associated with that scan cell. A delay defect bypass controller may be used to generate a bypass control signal for controlling the multiplexer between at least a first state in which the corresponding scan cell is not bypassed and a second state in which the corresponding scan cell is bypassed.

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: An integrated circuit comprises scan test circuitry and additional circuitry subject to testing utilizing the scan test circuitry. The scan test circuitry comprises scan cells configured to form scan chains. At least a given one of the scan cells is a multiple scan input scan cell having at least first and second scan inputs. In a first scan shift mode of operation, the given scan cell is configured with a first plurality of other scan cells into a scan chain of a first type using the first scan input. In a second scan shift mode of operation, the given scan cell is configured with a second plurality of other scan cells different than the first plurality of other scan cells into a scan chain of a second type using the second scan input.

Abstract: An integrated circuit comprises a memory or other circuit core having an input interface and an output interface, scan circuitry comprising at least one scan chain having a plurality of scan cells, and additional circuitry associated with at least one of the input interface and the output interface and testable utilizing said at least one scan chain. The scan circuitry further comprises a scan controller configured to control signal values applied to one or more signal lines of the input interface in conjunction with testing of the additional circuitry utilizing said at least one scan chain. For example, the scan controller may control signal values applied to respective address input and write enable signal lines in a manner that ensures that data written to a memory in a write operation of a given memory cycle can be read from the memory in a read operation of a subsequent memory cycle.

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 further comprises transition launch mode selection circuitry configured to provide independent selection between multiple transition launch modes for each of a plurality of clock domains of the integrated circuit. The multiple transition launch modes may include, for example, at least a launch-on-shift mode and a launch-on-capture mode. These transition launch modes provide different manners of launching a given signal transition via at least one of the scan cells in a corresponding one of the clock domains. The transition launch mode selection circuitry may be configured to generate from a common shift enable signal multiple independently controllable shift enable signals for respective ones of the clock domains of the integrated circuit.

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 a plurality of scan cells, with the scan chain being configured to operate as a serial shift register in a scan shift mode of operation and to capture functional data from at least a portion of the additional circuitry in a functional mode of operation. At least a given one of the scan cells of the scan chain comprises output control circuitry which is configured to disable a functional data output of the scan cell in the scan shift mode of operation and to disable a scan output of the scan cell in the functional mode of operation.

Abstract: An integrated circuit comprises a memory or other type of circuit core having an input interface and an output interface, built-in self-test circuitry configured for testing of the circuit core between its input and output interfaces in a built-in self-test mode of operation, and at least one scan chain having a plurality of scan cells. The scan cells of the scan chain are coupled to respective signal lines at the input and output interfaces and configured to allow capture of functional signal values from those signal lines in a functional mode of operation and shifting out of the captured functional signal values in a scan shift mode of operation. This allows detection of faults associated with functional paths of the interface that would otherwise not be detectable using the built-in self-test circuitry.

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 clock gating circuitry configured to control delivery of one or more of the clock signals along respective clock signal lines of the clock distribution network at least in part responsive to a scan shift control signal that is also utilized to cause the scan cells to form a serial shift register during scan testing. The clock gating circuitry may be used to determine whether a clock delay defect that causes a scan error during scan testing will also cause a functional error during functional operation, thereby improving yield in integrated circuit manufacturing.