A circuit comprises a plurality of clock control devices. Each of the clock control devices is configured to generate a scan test clock signal for a particular clock domain in the circuit and comprises circuitry configured to select clock pulses of a fast clock signal as scan capture clock pulses for the particular clock domain based on a particular clock pulse of a slow clock signal and a scan enable signal. The order and spacing between the groups of the scan capture clock pulses for different clock domains correspond to the order and spacing of the clock pulses of the slow clock signal.

The present application relates to a circuit simulation test method and apparatus, a device, and a medium. The method includes: creating a parametric data model, wherein the parametric data model is configured to generate preset write data based on a preset parameter; creating a test platform, wherein the test platform is configured to generate a test result based on the preset write data; creating an eye diagram generation module, wherein the eye diagram generation module is configured to generate a data eye diagram based on the test result; and conducting a simulation test, inputting the preset write data to the test platform and obtaining the test result, and generating the data eye diagram by using the eye diagram generation module.

A testkey includes two switching circuits and two compensation circuits. The first switching circuit transmits a test signal to a first DUT when the first DUT is being tested and functions as high impedance when the first DUT is not being tested. The second switching circuit transmits the test signal to a second DUT when the second DUT is being tested and functions as high impedance when the second DUT is not being tested. When the first DUT is not being tested and the second DUT is being tested, the first compensation circuit provides first compensation current for reducing the leakage current of the first switching circuit. When the first DUT is being tested and the second DUT is not being tested, the second compensation circuit provides second compensation current for reducing the leakage current of the second switching circuit.

A combinational circuit block has input pins configured to receive input digital signals and output pins configured to provide output digital signals as a function of the input digital signals received. A test input pin receives a test input signal. A test output pin provides a test output signal as a function of the test input signal received. A set of scan registers are selectively coupled to either the combinational circuit block or to one another so as to form a scan chain of scan registers serially coupled between the test input pin and the test output pin. The scan registers in the set of scan registers are clocked by a clock signal. At least one input register is coupled between the test input pin and a first scan register of the scan chain. The at least one input register is clocked by an inverted replica of the clock signal.

An integrated circuit includes a flip-flop circuit and a gating circuit. The flip-flop circuit is arranged to receive an input data for generating a master signal during a writing mode according to a first clock signal and a second clock signal, and to output an output data according to the first clock signal and the second clock signal during a storing mode. The gating circuit is arranged for generating the first clock signal and the second clock signal according to the master signal and an input clock signal. When the input clock signal is at a signal level, the first clock signal and the second clock signal are at different logic levels. When the input clock signal is at another signal level, the first clock signal and the second clock signal are at a same logic level determined according to a signal level of the master signal.

One aspect provides an FPGA chip mounted on a printed circuit board (PCB). The FPGA chip can include a joint test action group (JTAG) interface comprising a number of input/output pins and an enablement pin, and a control logic block coupled to the enablement pin of the JTAG interface. The control logic block can receive a control signal from an off-chip control unit and control a logical value of the enablement pin based on the received control signal, thereby facilitating the off-chip control unit to lock or unlock the JTAG interface. The FPGA chip can further include a detection logic block to detect an unauthorized access to the FPGA chip. An input to the detection logic is coupled to the enablement pin, and a conductive trace coupling the input of the detection logic block and the enablement pin is situated on an inner layer of the PCB.

A system, comprising: a plurality of first latches; a compressor circuit, coupled to the first latches, configured to compress an first signal having X bits from the first latches to a second signal having Y bits, wherein X and Y are positive integers and X is larger than Y; and at least one second latch, coupled to the compressor circuit, configured to receive the second signal to generate a scan output, wherein each of the first latches and the second latch forms a D flip flop. The system outputs the first signal but none of the scan output in a normal mode, and outputs the scan output but none of the first signal in a test mode.

A device test architecture and interface is provided to enable efficient testing embedded cores within devices. The test architecture interfaces to standard IEEE 1500 core test wrappers and provides high test data bandwidth to the wrappers from an external tester. The test architecture includes compare circuits that allow for comparison of test response data to be performed within the device. The test architecture further includes a memory for storing the results of the test response comparisons. The test architecture includes a programmable test controller to allow for various test control operations by simply inputting an instruction to the programmable test controller from the external tester. The test architecture includes a selector circuit for selecting a core for testing. Additional features and embodiments of the device test architectures are also disclosed.

An integrated circuit die includes a core fabric configurable to include an aging measurement circuit and a device manager coupled to the core fabric to operate the aging measurement circuit for a select period of time. The aging measurement circuit includes a counter to count transitions of a signal propagating through the aging measurement circuit during the select period of time when the aging measurement circuit is operating. The transitions of the signal counted by the counter during the select period of time are a measure of an aging characteristic of the integrated circuit die.

A clock self-testing method and circuit. The clock self-testing method includes introducing a first clock signal and a second clock signal, counting cycles of the first clock signal and the second clock signal respectively beginning at the same moment, and if one of the number of cycles of the first clock signal being counted and the number of cycles of the second clock signal being counted is equal to N, determining whether the remained number of cycles is in a count range from M to N. If the remained number of cycles is out of the count range from M to N, the first clock signal and the second clock signal have errors.