Lsi Corporation

Avago Technologies General IP (singapore) Pte. Ltd.

Prakash Krishnamoorthy

Ramesh C Tekumalla

Parag Madhani

Niranjan Anant Pol

Priyesh Kumar

Vijay Sharma

Vineet Sreekumar

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.

Instruction address encoding and decoding based on program construct groups

An integrated circuit comprises scan test circuitry and at least one circuit core coupled to the scan test circuitry. The scan test circuitry comprises input and output scan chains coupled to respective input and output interfaces of the circuit core via respective functional logic blocks, and interface signal selection circuitry. The interface signal selection circuitry is configured to select a particular one of a functional input signal and a plurality of scan test input signals for application to one or more designated input signal lines of the input interface of the circuit core responsive to one or more control signals. By way of example only, the first and second scan test input signals may comprise respective first and second distinct address values and the designated input signal lines of the input interface of the circuit core may comprise address input signal lines of an embedded memory.

At-speed scan testing of interface functional logic of an embedded memory or other circuit core

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.

Integrated circuit having clock gating circuitry responsive to scan shift control signal

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.

Clock control for reducing timing exceptions in scan testing of an integrated circuit

An integrated circuit comprises scan test circuitry and additional internal circuitry subject to testing utilizing the scan test circuitry. The scan test circuitry comprises a plurality of scan chains, with each such scan chain comprising a plurality of flip-flops configurable to operate as a serial shift register. The plurality of scan chains are arranged in sets of two or more parallel scan chains. The scan test circuitry further comprises multiplexing circuitry, including a plurality of multiplexers each associated with a corresponding one of the sets of parallel scan chains and configured to multiplex scan test outputs from the parallel scan chains within the corresponding one of the sets of parallel scan chains. In one embodiment, one or more of the sets of parallel scan chains comprise respective pairs of parallel scan chains with each such pair corresponding to a single original scan chain. A given one of the pairs of parallel scan chains comprises an even scan chain and an odd scan chain, formed by reordering the corresponding single original scan chain.

Integrated circuit comprising scan test circuitry with parallel reordered scan chains

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.

Scan test circuitry configured for bypassing selected segments of a multi-segment scan chain

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.

Coding circuitry for difference-based data transformation

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.

Scan test circuitry configured to prevent capture of potentially non-deterministic values

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.

Integrated circuit with transition control circuitry for limiting scan test signal transitions during scan testing

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.

Scan test circuitry with delay defect bypass functionality

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.

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Bethlehem, PA, United States of America

Prakash Krishnamoorthy