A core partition circuit comprises a first decompression circuit, a second decompression circuit, a first switching circuit, an wrapper scanning circuit, a first compression circuit, a second compression circuit and a second switching circuit. The first and second decompression circuits decompress an input signal. The first switching circuit outputs the output signal of the first decompression circuit or the second decompression circuit according to a first control signal. The wrapper scanning circuit receives the output signal of the first decompression circuit or the second decompression circuit to scan the internal or the port of the core partition circuit. The first and second compression circuits respectively compress the internal logic and the port logic of the core partition circuit. The second switching circuit outputs the compressed internal logic or port logic of the core partition circuit according to the first control signal.

A system on chip includes a one-time programmable (OTP) memory configured to store secure data, an OTP controller including at least one shadow register configured to read the secure data from the OTP memory and to store the secure data, a power management unit configured to receive an operation mode signal from an external device and to output test mode information indicating whether an operation mode is a test mode according to the operation mode signal and a test valid signal corresponding to the secure data, and a test circuit configured to receive the test mode information from the power management unit, to receive test data from the external device, and to output a scan mode signal and a test mode signal according to the test data and a test deactivation signal, wherein the test deactivation signal corresponds to development state data indicating a chip development state in the secure data.

A circuit for implementing a scan chain in programmable resources of an integrated circuit is described. The circuit comprises a programmable element configured to receive an input signal and generate an output signal based upon the input signal; a selection circuit configured to receive the output signal generated by the programmable element at a first input and to receive a scan chain input signal at a second input, wherein the selection circuit generates a selected output signal in response to a selection circuit control signal; and a register configured to receive the selected output signal of the selection circuit.

A chip, a chip testing method and an electronic device are provided. The chip includes a combinational logic and a data path gating; the data path gating includes a first input terminal and an output terminal, the first input terminal of the data path gating detects a test enable signal, and the output terminal of the data path gating is connected to the combinational logic; the test enable signal is used to switch a test mode of the chip; the data path gating is configured to output a data path gating control signal to the combinational logic, in a case where the detected test enable signal indicates that a current test mode is irrelevant to a data path function of the combinational logic; and the combinational logic is configured to disable the data path function after receiving the data path gating control signal, to disable data path toggling.

A method and circuits are provided for implementing enhanced scan data testing using an XOR network to prioritize faults to be simulated during diagnostic isolation, and reducing the number of faults requiring re-simulation. A test is run, scan data are applied to scan channels using the XOR network and the output scan data are unloaded. A list of possible faults is identified based on pin flips, and the possible faults to be simulated during diagnostic isolation are prioritized by a number of occurrences in the list, and possible faults are further graded to reduce the number of possible faults requiring re-simulation.

A scan chain architecture with lowered power consumption comprises a multiplexer selecting between a functional input and a test input. The output of the multiplexer is coupled to a low threshold voltage latch and, in test mode, to a standard threshold voltage latch. The low threshold voltage latch and standard threshold voltage latch are configured to store data when a clock input falls, using a master latch functional clock M_F_CLK, master latch test clock M_T_CLK, slave latch functional clock S_F_CLK, and slave latch test clock S_T_CLK. The slave latch has lower power consumption than the master latch.

Various aspects of the disclosed technology relate to machine learning-based chain diagnosis. Faults are injected into scan chains in a circuit design. Simulations are performed on the fault-injected circuit design to determine test response patterns in response to the test patterns which are captured by the scan chains. Observed failing bit patterns are determined by comparing the unloaded test response patterns with corresponding good-machine test response patterns. Bit-reduction is performed on the observed failing bit patterns to construct training samples. Using the training samples, machine-learning models for faulty scan cell identification are trained. The bit reduction comprises pattern-based bit compression for good scan chains or cycle-based bit compression for the good scan chains. The bit reduction may further comprise bit-filtering. The bit-filtering may comprises keeping only sensitive bits on faulty scan chains for the training samples construction.

A circuit for implementing a scan chain in an integrated circuit having a clock domain crossing is described. The circuit comprises a first dual-edge storage circuit configured to receive an input signal at a scan input and to receive a first clock signal in a first clock domain at a clock input; a storage element having a data input configured to receive an output of the first dual-edge storage circuit; a second dual-edge storage circuit configured to receive an output of the storage element at a scan input and to receive a second clock signal in a second clock domain at a clock input; and a pulse generator configured to provide, to a clock input of the storage element, a pulse signal having a pulse width selected to enable the second dual-edge storage element to store the output of the first dual-edge storage element.

Testing of die on wafer is achieved by; (1) providing a tester with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuitry, (2) providing die on wafer with the capability of externally communicating JTAG test signals using simultaneously bidirectional transceiver circuitry, and (3) providing a connectivity mechanism between the bidirectional transceiver circuitry's of the tester and a selected group or all of the die on wafer for communication of the JTAG signals.

A failure diagnostic apparatus includes a path calculation unit which calculates, for each input pattern to a diagnosis target cell, a path affecting an output value of the diagnosis target cell when a failure is assumed as an activation path, a path classification unit which classifies the activation path associated with the input pattern for which the diagnosis target cell has passed a test and the activation path associated with the input pattern for which the diagnosis target cell has failed the test, a path narrowing unit which calculates a first failure candidate path, a second failure candidate path and a normal path of the diagnosis target cell based on classified activation paths, and a result output unit which outputs information on the first failure candidate path, the second failure candidate path and the normal path.