In a first embodiment a TAP 318 of IEEE standard 1149.1 is allowed to commandeer control from a WSP 202 of IEEE standard P1500 such that the P1500 architecture, normally controlled by the WSP, is rendered controllable by the TAP. In a second embodiment (1) the TAP and WSP based architectures are merged together such that the sharing of the previously described architectural elements are possible, and (2) the TAP and WSP test interfaces are merged into a single optimized test interface that is operable to perform all operations of each separate test interface.

In various examples, a test system is provided for executing built-in-self-test (BIST) according to JTAG and IEEE 1500 on chips deployed in-field. Hardware and software selectively connect onto the IEEE 1500 serial interface for running BIST while the chip is being used in deploymentsuch as in an autonomous vehicle. In addition to providing a mechanism to connect onto the serial interface, the hardware and software may reduce memory requirements and runtime associated with running the test sequences, thereby making BIST possible in deployment. Furthermore, some embodiments include components configured to store functional states of clocks, power, and input/output prior to running BIST, which permits restoration of the functional states after the BIST.

A test system is provided. The test system includes a printed circuit board (PCB) and a plurality of integrated circuits (ICs) mounted on the PCB. A first IC of the plurality includes a first test circuit having a first test access port (TAP) controller. A second IC of the plurality includes a second test circuit having a second TAP controller and an embedded tester having a test data output coupled to a test data input of the first TAP controller by way of a link circuit. The embedded tester is configured to provide test control signals to the first TAP controller and the second TAP controller.

A test system is provided. The test system includes a printed circuit board (PCB) and a plurality of integrated circuits (ICs) mounted on the PCB. A first IC of the plurality includes a first test circuit having a first test access port (TAP) controller. A second IC of the plurality includes a second test circuit having a second TAP controller and an embedded tester having a test data output coupled to a test data input of the first TAP controller by way of a link circuit. The embedded tester is configured to provide test control signals to the first TAP controller and the second TAP controller.

This disclosure describes a test architecture that supports a common approach to testing individual die and dies in a 3D stack arrangement. The test architecture uses an improved TAP design to facilitate the testing of parallel test circuits within the die.

Invention achieves reduced amount of terminals to control a test mode, test function and test results of a given standard for at least one wrapped core (40,100) (a core 100 surrounded by a wrapper boundary register (40) as wrapper chain). Test flexibility and speed of testing the core (100) are also improved. Suggested serial test interface comprises a state machine (210) and an instruction register (213) for wrapper-instructions, supplied through a single physical data input terminal (1a). The state machine (210) reads wrapper-instructions held by the instruction register (213) and generates on-chip wrapper control signals (30) of the given standard for the wrapper boundary register (40) of the core (100). At least one wrapper-instruction read from the Instruction Register (213) provides at least one wrapper control signal (30). The single input terminal (1a) also supplies an input test signal SDI for coupling to the wrapper boundary register (40) as on chip logical input test signal WSI. A single output terminal (1b) returns an output test signal SDO from an output WSO of the wrapper boundary register (40). Invention may apply to IEEE 1500 control signals.

In various examples, a test system is provided for executing built-in-self-test (BIST) according to JTAG and IEEE 1500 on chips deployed in-field. Hardware and software selectively connect onto the IEEE 1500 serial interface for running BIST while the chip is being used in deploymentsuch as in an autonomous vehicle. In addition to providing a mechanism to connect onto the serial interface, the hardware and software may reduce memory requirements and runtime associated with running the test sequences, thereby making BIST possible in deployment. Furthermore, some embodiments include components configured to store functional states of clocks, power, and input/output prior to running BIST, which permits restoration of the functional states after the BIST.

This disclosure describes a test architecture that supports a common approach to testing individual die and dies in a 3D stack arrangement. The test architecture uses an improved TAP design to facilitate the testing of parallel test circuits within the die.

In a first embodiment a TAP 318 of IEEE standard 1149.1 is allowed to commandeer control from a WSP 202 of IEEE standard P1500 such that the P1500 architecture, normally controlled by the WSP, is rendered controllable by the TAP. In a second embodiment (1) the TAP and WSP based architectures are merged together such that the sharing of the previously described architectural elements are possible, and (2) the TAP and WSP test interfaces are merged into a single optimized test interface that is operable to perform all operations of each separate test interface.

In a first embodiment a TAP 318 of IEEE standard 1149.1 is allowed to commandeer control from a WSP 202 of IEEE standard P1500 such that the P1500 architecture, normally controlled by the WSP, is rendered controllable by the TAP. In a second embodiment (1) the TAP and WSP based architectures are merged together such that the sharing of the previously described architectural elements are possible, and (2) the TAP and WSP test interfaces are merged into a single optimized test interface that is operable to perform all operations of each separate test interface.