Lsi Corporation

Intel Corporation

Avago Technologies General IP (singapore) Pte. Ltd.

Sreejit Chakravarty

Alexander Y Tetelbaum

Sujit T Zachariah

Sorin Iacobovici

Amy L Santoni

Michael Neve De Mevergnies

Fan Yang

Ramasubramanian Rajamani

Neel Piyush Shah

Carl D Roth

Oscar Mendoza

Bryan J Gran

Kirk S Yap

Amit D Sanghani

Asad Azam

Arun K Gunda

Fei Su

Anubhav Sinha

Narendra Devta-Prasanna

Rakesh Reddy Kandula

R Selvakumar Raja Gopal

Puneet Gupta

John Cruz Mejia

Terrence Huat Hin Tan

Kaitlyn Chen

Wei Ming Lim

Sudheer V Badana

Adithya B S

Narendra B Devta-Prasa

Nicholas A Callegari

The disclosed embodiments relate to method, apparatus and system for testing memory circuitry and diagnostic components designed to test the memory circuitry. The memory may be tested regularly using Memory Built-In Self-Test (MBIST) to detect memory failure. Error Correction Code (ECC)/Parity is implemented for SRAM/Register Files/ROM memory structures to protect against transient and permanent faults during runtime. ECC/Parity encoder and decoder logic detect failure on both data and address buses and are intended to catch soft error or structural fault in address decoding logic in SRAM Controller, where data may be read/written from/to different locations due to faults. ECC/parity logic on the memory structures are subject to failures. In certain exemplary embodiments, an array test controller is used to generate and transmit error vectors to thereby determine faulty diagnostic components. The test vectors may be generated randomly to test the diagnostic components during run-time for in-field testing.

Methods, systems and apparatus for in-field testing for generic diagnostic components

A die-to-die repeater circuit includes a transmit circuit coupled to a die-to-die interconnect, the transmit circuit including at least one flip flop to function as a part of a linear feedback shift register (LFSR) to transmit a value across the die-to-die interconnect for design for test (DFT) to check proper operation of the die-to-die interconnect, and a receive circuit coupled to the die-to-die interconnect, the receive circuit including at least one flip flop to function as part of a multiple input shift register (MISR).

Test architecture for die to die interconnect for three dimensional integrated circuits

A processor, including: a core; system test circuitry, the system test circuitry to be locked during operational processor operation; reset circuitry including a kick-off test (KOT) input, the reset circuitry to detect a reset with the KOT input asserted, and to initiate an in-field system test (IFST) mode; a test interface controller to receive in IFST mode an encrypted test packet having a signature, verify the signature of the test packet, and decrypt the test packet; and IFST control circuitry to cause the system test circuitry to perform an IFST test according to the decrypted test packet and to log or report results.

In-field system testing

A processor, including: a core; system test circuitry, the system test circuitry configured to be locked except during an in-field system test (IFST) mode; IFST control circuitry; and a test interface controller, including: a data interface to receive a test packet; a parser to parse the test packet into a key, a signature, and a stored hash-of-hashes; a decryption circuit to decrypt the signature according to the key and to generate a computed hash-of-hashes; a hash circuit to verify the stored hash-of-hashes against the computed hash-of-hashes; and an IFST interface, wherein the test interface controller is to signal the IFST control circuitry to place the system test circuitry in IFST mode.

In-field system test security

Methods and systems for generating data transformations to improve ROM yield and programming time. A bit flip register can be configured in association with the ROM and a binary string can be read into the bit flip register on reset. Subsequently, data output from the ROM can be selectively complemented utilizing a content of the bit flip register and the content of the bit flip register can be programmed into the ROM in order to reduce programming time for each ROM. A defective cell can be tolerated by selectively flipping a column with respect to the defective cell to improve yield. A built-in self-test (BIST) engine that generates addresses up to and including content of an address limiting register can be employed to limit the ROM access to a programmed part during testing in order to tolerate defects in any unused location.

Data transformations to improve ROM yield and programming time

A self-test module for use in an electronic device includes a test controller and a memory. The memory is configured to receive test vectors from the test controller. A comparator is configured to receive the test data from the memory via an output data path. A strobing buffer is located in the output data path between an output from the memory and an input to the comparator. The strobing buffer is configured to selectively enable the test vectors to propagate from the memory output to the comparator input.

Low-cost design for register file testability

A multiport latch-based memory device includes a latch array, a plurality of first multiplexers, and a second multiplexer. The latch array is responsive to output data from an input data register in a functional mode associated with the latch-based memory device. The plurality of first multiplexers is responsive to output data from the latch array in the functional mode. The plurality of first multiplexers is responsive to output data from the input data register in a test mode associated with the latch-based memory device. The second multiplexer selectively provides output data from the plurality of first multiplexers to the input data register in the test mode, thereby providing a data path bypassing the latch array in the test mode. Embodiments of a corresponding method and computer-readable medium are also provided.

Victim port-based design for test area overhead reduction in multiport latch-based memories

A scan cell is configured to receive first, second and third data bits at respective first, second and third data inputs. A control input is configured to receive a control signal. Latching logic is configured to latch data received at the first and second latch inputs to a scan cell output. The first latch input is configured to receive the first data bit. Selection logic is configured to select between the second and third data bits depending on a state of the control signal, and to provide the selected bit to the second latch input.

Scan cell designs with serial and parallel loading of test data

An integrated circuit chip that supports stored-pattern (SP) logic built-in self-testing (LBIST) includes a device under test (DUT) and a test controller. System-level SP LBIST testing is performed using an external, system ATE (automated test equipment) that transmits test input data to the test controller for application to the DUT, which generates test output data that is transmitted from the test controller to the system ATE, which performs golden signature comparisons on the test output data. During system-level DUT testing, all communications between the system ATE and the chip are via a single interface, such as a conventional, serial JTAG port.

Stored-pattern logic self-testing with serial communication

A path monitor, a method of monitoring a path, an integrated circuit and a library of standard logic elements. In one embodiment, the path monitor includes: (1) a delay element having an input couplable to an input of a clocked flip-flop associated with a path to be monitored and configured to provide a predetermined delay and (2) a clocked exclusive OR gate having a clock input, a first input coupled to an output of the delay element, a second input couplable to the output of the clocked flip-flop and an output at which the clocked exclusive OR gate is configured to respond to a clock signal to provide an error signal only when logic levels of the first input and the second input differ.

Critical path monitor for an integrated circuit and method of operation thereof

A stored-pattern logic self-test system includes a memory, a device under test and a test controller. The memory stores test pattern data including test stimuli. The device under test includes a scan chain and a test access port configurable to control operation of the scan chain. The test controller is configured to test the device under test by controlling the memory to output the test stimuli to the device under test. The test controller controls the test access port to load the test stimuli into the scan chain, and receives and evaluates response data from the device under test.

Logic BIST for system testing using stored patterns

A timing error sampling generator, a method of performing timing tests and a library of cells are provided. In one embodiment, the timing error sampling generator includes: (1) a hold delay element having an input and an output and configured to provide a hold violation delayed signal at said output by providing a first predetermined delay to a clock signal received at said input, said first predetermined delay corresponding to a hold violation time for a path to be monitored and (2) a hold logic element having a first input coupled to said input of said hold delay element, a second input coupled to said output of said hold delay element and an output at which said hold logic element is configured to respond to said first and second inputs to provide a clock hold signal when logic levels at said first and second inputs are at a same level.

Timing error sampling generator and a method of timing testing

An electronic design automation (EDA) tool and a method of employing unsensitized critical path information to reduce leakage power in a circuit. In one embodiment, the EDA tool includes: (1) an unsensitizable path identifier configured to receive information regarding designed devices in a circuit and information regarding identified critical paths therein, analyze a logical behavior of the circuit and identify critical and noncritical gates in unsensitizable ones of the critical paths thereof and (2) a transistor designator coupled to the unsensitizable path identifier and configured to designate relatively low threshold voltage transistors for use in the critical gates and designate relatively high threshold voltage transistors for use in the noncritical gates.

Electronic design automation tool and method for employing unsensitized critical path information to reduce leakage power in an integrated circuit

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.

Test technique to apply a variable scan clock including a scan clock modifier on an integrated circuit

A comparator determines the fidelity of a response vector received from a memory under test. The comparator includes a first logic gate configured to output a first value that is the logical OR of a first proper subset of bits of the response vector. A second logic gate is configured to output a second value that is the logical NAND of the proper subset of bits. A first multiplexer is configured to select between the first and second values based on the value of a first bit of a check vector corresponding to the response vector.

Growing community of inventors

Mountain View, CA, United States of America

Sreejit Chakravarty