A boundary scan test method is used to test connectivity of a pad having a direct connection to user logic. The method comprises the following steps: configuring an FPGA to enter a test mode; generating by means of user logic, a boundary scan chain for a boundary scan test; loading a boundary scan test instruction to the FPGA, and loading a PRELOAD instruction to a device having a pad to be tested for connectivity; sending, via a TDI port, a first test vector to the pad; performing the boundary scan test, and loading an EXTEST instruction to the device having the pad; and removing first response data from a TDO port, and performing response analysis and fault diagnosis.

Sensor data relating to operating conditions for an integrated circuit are read out through scan chains. Scan tests are run on an integrated circuit containing logic circuits that implement logic functions. The logic circuits are interconnected to form scan chains which are used in running the scan tests. The scan test data resulting from the scan tests is read out from the logic circuits through these scan chains. During the scan tests, sensor blocks capture measurements of the operating conditions for the logic circuits. The operating conditions may include process, voltage and/or temperature conditions, for example. The sensor blocks are also interconnected to form one or more scan chains, and sensor data produced from the captured measurements is read out through these scan chains concurrently with the read out of the scan test data.

A device comprising includes an output terminal and a first current path from the output terminal to a first reference voltage. The first current path includes a series connection of current electrodes of a first transistor and a second transistor. The first transistor receives at a control electrode a signal to set a desired level of current to be conducted by the first current path. The second transistor generates at a control electrode a feedback signal indicative of an actual current conducted by the first transistor.

A data failure detection circuit of embodiments includes a monitor signal generation circuit configured to generate a monitor signal to be used to sense failures of a plurality of test mode signals to be respectively input to a plurality of modules, a cascade connection circuit configured to sense a failure of each of the test mode signals and including a plurality of OR circuits, and a comparison circuit configured to compare an output signal from the cascade connection circuit with the monitor signal to determine whether or not a failure exists. In the cascade connection circuit, a plurality of OR circuits are connected in cascade, and the monitor signal is input to one of the OR circuits in a first stage.

A method for defect identification for an integrated circuit includes determining a defect ranking technique, applying at least two defect identification techniques and generating a defect report corresponding to each technique, comparing the defect reports and generating probable defect locations, prioritizing the probable defect locations according to the defect ranking technique; and generating a report of the prioritized probable defect locations.

A semiconductor device addresses to a problem in which a current consumption variation rate increases during BIST execution causing resonance noise generation in a power supply line. The semiconductor device includes a self-diagnosis control circuit, a scan target circuit including a combinational circuit and a scan flip-flop, and an electrically rewritable non-volatile memory. A scan chain is configured by coupling a plurality of the scan flip-flops. In accordance with parameters stored in the non-volatile memory, the self-diagnosis control circuit can change a length of at least one of a scan-in period, a scan-out period and a capture period, and can also change a scan start timing.

A method is provided and includes several operations: testing multiple scan chains in multiple shift cycles to obtain multiple values; determining at least one fail chain in the scan chains and determining at least one fail shift cycle corresponding to at least one fail value in the values; mapping the at least one fail chain and the at least one fail shift cycle to the scan chains to identify the at least one fail flip flop; and identifying at least one fault site corresponding to the at least one fail flip flop.

A device comprising includes an output terminal and a first current path from the output terminal to a first reference voltage. The first current path includes a series connection of current electrodes of a first transistor and a second transistor. The first transistor receives at a control electrode a signal to set a desired level of current to be conducted by the first current path. The second transistor generates at a control electrode a feedback signal indicative of an actual current conducted by the first transistor.

A circuit debugging method includes: utilizing a debugging circuit to determine an operating status of a specific circuit to generate a result; utilizing a register located in a scan chain path to store the result, wherein the scan chain path is arranged for a scan test; and utilizing an output pad located in the scan chain path to output the result, wherein the result is arranged to be indicative of the operating status of the specific circuit.

A method of detecting faults in a register bank is disclosed. The register bank includes at least one chain of registers. The method comprises sequentially shifting parameters stored in each register of the chain to an output node of the chain and inverting each parameter and feeding each parameter back to an input node of that chain, and sequentially shifting the inverted parameters through the chain until all the non-inverted parameters have been output at the output node. A first checksum of the parameters output at the output node is calculated. The inverted parameters in each register of the chain are sequentially shifted to the output node of the chain. A second checksum of the inverted parameters output at the output node is calculated, and the first and second checksums are compared.