Abstract: Methods and systems generate a manufacturing test of a programmable integrated circuit and optionally test the programmable integrated circuit with the manufacturing test. A netlist is generated that represents a specific user design implemented in programmable resources of the programmable integrated circuit. The netlist represents user registers that are implemented in a portion of the logic registers of the programmable logic resources. A virtual scan chain is added to the netlist. Scan-test vectors are generated from the netlist using automatic test pattern generation (ATPG). The scan-test vectors serially scan the portion of the logic registers via the virtual scan chain. The scan-test vectors are converted into access-test vectors that access the portion of the logic registers via a configuration port of the programmable integrated circuit. The programmable integrated circuit is optionally tested for a manufacturing defect with the access-test vectors.

Abstract: An MOS transistor is programmed in a non-volatile memory cell. A storage capacitor in the non-volatile memory cell is used to enhance programming efficiency by providing additional charge to the programming terminal of the MOS transistor during breakdown of the gate dielectric, thus avoiding soft programming faults. In a particular embodiment the storage capacitor is a second MOS transistor having a thicker gate dielectric layer than the dielectric layer of the programmable MOS transistor.

Abstract: A method of testing of an embedded core of an integrated circuit (“IC”) is described. An IC has a hardwired embedded core and memory coupled to each other in the IC. The method includes writing a test vector to the memory while the embedded core is operative. The test vector is input from the memory to the embedded core to mimic scan chain input to the embedded core. A test result is obtained from the embedded core responsive in part to the test vector input.

Abstract: A circuit may be used for testing for faults in a programmable logic device. The circuit may include a clock generator coupled to receive a reference clock signal and generate a high speed clock signal; a circuit under test coupled to receive selected pulses of the high speed clock signal; and a programmable shift register coupled to receive a pulse width selection signal and generate an enable signal for selecting the pulses the high speed clock signal, wherein the pulse width of the enable signal is selected based upon the value of the pulse width selection signal. A method of testing for faults in a programmable logic device is also disclosed.

Abstract: A method of testing a programmable device begins by programming at least a portion of the programmable device in accordance with at least a portion of an application to produce a programmed circuit, wherein the programmed circuit includes an input sequential element and an output sequential element. The method continues by providing a test input to the programmed circuit. The method continues by triggering the input sequential element to temporarily store the test input based on a first edge of the test clock. The method continues by triggering the output sequential element to temporarily store a test output of the programmed circuit based on a second edge of the test clock. The method continues by capturing the test output of the programmed circuit in accordance with the second edge of the test clock.

Abstract: A MOS transistor is used as a programmable three-terminal non-volatile memory element. The gate dielectric layer of the MOS transistor has a first portion with a relatively higher dielectric breakdown strength than a second portion. The location of the second portion is chosen so as to avoid having the gate dielectric layer break down near the edge of the active area or isolation area during programming. In a particular embodiment, the gate dielectric layer is silicon oxide, and the first portion is thicker than the second portion.

Abstract: An MOS transistor is programmed in a non-volatile memory cell. A storage capacitor in the non-volatile memory cell is used to enhance programming efficiency by providing additional charge to the programming terminal of the MOS transistor during breakdown of the gate dielectric, thus avoiding soft programming faults. In a particular embodiment the storage capacitor is a second MOS transistor having a thicker gate dielectric layer than the dielectric layer of the programmable MOS transistor.

Abstract: A method of testing a programmable device begins by programming at least a portion of the programmable device in accordance with at least a portion of an application to produce a programmed circuit, wherein the programmed circuit includes an input sequential element and an output sequential element. The method continues by providing a test input to the programmed circuit. The method continues by triggering the input sequential element to temporarily store the test input based on a first edge of the test clock. The method continues by triggering the output sequential element to temporarily store a test output of the programmed circuit based on a second edge of the test clock. The method continues by capturing the test output of the programmed circuit in accordance with the second edge of the test clock.

Abstract: SEU-hardening series resistances loads are formed within the gate structures of cross-coupled inverters of a latch. For some embodiments, the gate contact for the input of each cross-coupled inverter has a sufficiently high resistance to provide the SEU-hardening series resistance. For other embodiments, a conductive trace layer coupled to the input of each cross-coupled inverter includes a high-resistivity portion that provides the SEU-hardening series resistance.

Abstract: A PMOS transistor is programmed as a non-volatile memory element by operating the PMOS transistor in accumulation mode. This facilitates merging the source and drain regions to form a low-resistance path because most heating occurs on the channel side of the gate dielectric, rather than on the gate terminal side. In a particular embodiment, boron is used as the dopant. Boron has a higher diffusivity than arsenic or phosphorous, which are typical n-type dopants. Boron's higher diffusivity promotes merging the source and drain regions.

Abstract: A storage transistor is programmed as a non-volatile memory element by biasing the source and drain while a programming voltage is applied to the gate. The substrate is held at a different potential than the source/drain to insure that the greatest difference in voltage during the programming step occurs between the channel region and the gate, rather than the gate and the source/drain. The programming voltage heats the channel region to form a non-volatile low-resistance connection between the source and drain, which is read to determine the programmed state.

Abstract: A Built-in Self Test (BIST) system is provided in a Field Programmable Gate Array (FPGA) that can adjust test signal patterns provided for testing after partial reconfiguration of the FPGA. The BIST system includes a decoder that monitors I/O signals and provides an output indicating when I/O signals change indicating partial reconfiguration has occurred. The decoder output is provided to a BIST test signal generator providing signals to an IP core of the FPGA as well as a BIST comparator for monitoring test results to change test signals depending on the partial configuration mode.

Abstract: A method and apparatus are disclosed that simplify and reduce the time required for detecting faults in a programmable device such as a programmable logic device (PLD) by utilizing fault coverage information corresponding to a plurality of test patterns for the PLD to reduce the set of potential faults. For one embodiment, each test pattern is designated as either passing or failing, the faults that are detectable by at least two failing test patterns and the faults that are not detectable by any passing test patterns are eliminated, and the remaining faults are diagnosed. For another embodiment, the faults detectable by each failing test pattern are diagnosed to generate corresponding fault sets, and the faults not common to the fault sets and not detectable by one or more of the failing test patterns are eliminated.

Abstract: SEU-hardening series resistances loads are formed within the gate structures of cross-coupled inverters of a latch. For some embodiments, the gate contact for the input of each cross-coupled inverter has a sufficiently high resistance to provide the SEU-hardening series resistance. For other embodiments, a conductive trace layer coupled to the input of each cross-coupled inverter includes a high-resistivity portion that provides the SEU-hardening series resistance.

Abstract: Methods of testing for shorts (e.g., bridging defects) between interconnect lines in an integrated circuit. For example, in a design implemented in a programmable logic device (PLD), some interconnect lines are used and others are unused. To test for shorts between the used and unused interconnect lines, both used and unused interconnect lines are driven to a first logic level, and the leakage current is measured. The used interconnect lines are driven to a second logic level, while the unused lines remain at the first logic level. The current is again measured, and the difference between the two measurements is determined. If the difference exceeds a predetermined threshold, the device design combination is rejected. Some embodiments provide methods of testing for shorts between used and unused interconnect lines for a design targeted to a partially defective PLD.

Abstract: Disclosed are methods for utilizing programmable logic devices that contain at least one localized defect. Such devices are tested to determine their suitability for implementing selected designs that may not require the resources impacted by the defect. If the FPGA is found to be unsuitable for one design, additional designs may be tested. The test methods in some embodiments employ test circuits derived from a user's design to verify PLD resources required for the design. The test circuits allow PLD vendors to verify the suitability of a PLD for a given user's design without requiring the PLD vendor to understand the user's design.

Abstract: Disclosed are methods for utilizing programmable logic devices that contain at least one localized defect. Such devices are tested to determine their suitability for implementing selected designs that may not require the resources impacted by the defect. If the FPGA is found to be unsuitable for one design, additional designs may be tested. The test methods in some embodiments employ test circuits derived from a user's design to verify PLD resources required for the design. The test circuits allow PLD vendors to verify the suitability of a PLD for a given user's design without requiring the PLD vendor to understand the user's design.

Abstract: Disclosed are methods for utilizing programmable logic devices that contain at least one localized defect. Such devices are tested to determine their suitability for implementing selected designs that may not require the resources impacted by the defect. If the FPGA is found to be unsuitable for one design, additional designs may be tested. The test methods in some embodiments employ test circuits derived from a user's design to verify PLD resources required for the design. The test circuits allow PLD vendors to verify the suitability of a PLD for a given user's design without requiring the PLD vendor to understand the user's design.

Abstract: A new method to test short faults in a programmable logic device is described. The line segments under test are connected together to form a conducting chain. All the line segments neighboring to the conducting chain are tied to a known state. A test vector is applied to the programmable logic device. The state of the line under test is measured. If it is the same as the known state, the programmable logic device is likely to have faults.

Abstract: The location of short and open faults in a programmable logic device can be precisely located. The programmable logic device contains a plurality of nets, and each net contains a plurality of PIPs and connected line segments. A faulty net is first identified using conventional methods. A new design is constructed from a faulty net by replacing one of the plurality of line segments or PIPs with an alternative line segment/PIP. The mew design is tested to determine if the fault has been removed as a result of the replacement. If the fault is not removed, another line segment/PIP is replaced. This process is repeated until a design without fault is found. The location of the faulty line segment/PIP can be easily deduced.