International Business Machines Corporation

Xilinx, Inc.

Thomas Anderson Dick

Anthony Correale, Jr

Robert K Montoye

Nigel G Herron

Eric Thorne

Qingqi Wang

Les Mark DeBruyne

Sven Eric Meier

Waleed K Al-Assadi

Jay Donnelly Grollimund

A scannable limited switch dynamic logic (LSDL) circuit including a data input and a data output, a combinational logic circuit in communication with the data input, a pre-charge circuit in communication with the combinational logic circuit, a footer circuit in communication with the combinational logic, a keeper circuit in communication with the combinational logic circuit and the pre-charge circuit, a scan input connected to the data input, a scan input circuit in communication with the scan input, the combinational logic circuit, the pre-charge circuit, and the keeper circuit, a modified inverter circuit in communication with the combinational logic circuit, the pre-charge circuit, the keeper circuit, and the scan input circuit, a parallel gate circuit in communication with the modified inverter circuit, a series gate circuit in communication with the modified inverter circuit and the parallel gate circuit, a feedback inverter connected between an internal node and a feedback node, and an output buffer connected between the internal node and the data output.

Scannable limited switch dynamic logic (LSDL) circuit

A circuit that includes a core device that is embedded within fixed interfacing logic circuitry that, in turn, is embedded in an FPGA fabric. The FPGA fabric may be configured into a test mode of operation to test either the embedded device or fixed logic devices formed within the fixed interfacing logic. While the FPGA is configured in a test mode, test circuitry and communication paths are made present within the fixed interfacing logic circuitry to facilitate the testing. Additionally, the test circuitry comprises isolation circuitry that is formed between various modules and circuits that are to be tested to isolate the device under test and to produce test signals thereto and there from during testing operations.

Testing a programmable logic device with embedded fixed logic using a scan chain

A semiconductor device is disclosed that include a built-in self test system. The device comprises a logic function and a self test engine coupled and integrated with the logic device. The device includes a performance code storage coupled and integrated with the logic function. The performance code storage contains at least one critical path pattern that will be run on the logic function to determine the performance of the logic function when the self test engine causes the logic function to be in a performance test mode. In summary, a performance sort/validate integrated custom logic device, like a microprocessor core can be tested without the need for a separate, high-performance tester. A performance built-in self test (PBIST) approach provides a basic test procedure to be utilized within the device. An integrated memory array, such as the L1-cache, is provided wherein a select set of SRAM memory words are preconditioned at the time of manufacture to contain predefined functional patterns.

Performance built-in self test system for a device and a method of use

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Raleigh, NC, United States of America

Thomas Anderson Dick