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 circuity, 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.

This disclosure describes die test architectures that can be implemented in a first, middle and last die of a die stack. The die test architectures are mainly the same, but for the exceptions mentioned in this disclosure.

The disclosure describes a novel method and apparatuses for allowing a controller to select and access different types of access ports in a device. The selecting and accessing of the access ports is achieved using only the dedicated TDI, TMS, TCK, and TDO signal terminals of the device. The selecting and accessing of device access ports can be achieved when a single device is connected to the controller, when multiple devices are placed in a daisy-chain arrangement and connected to the controller, or when multiple devices are placed in a addressable parallel arrangement and connected to the controller. Additional embodiments are also provided and described in the disclosure.

A method for measuring (and controlling) a characteristic performance parameter Γ.sub.s of a device under test (DUT) having an input port (at the minimum). The method involves connecting the input port of the DUT to a signal generator, subjecting the DUT to a large signal input test signal, and executing a first measurement of the incident wave and reflected wave at a DUT input reference plane. The method further involves subjecting the DUT to a perturbation signal combined with the large signal input test signal, and executing a second measurement of the incident wave and reflected wave at the DUT input reference plane, and determining the characteristic performance parameter from the first measurement and the second measurement.

This disclosure describes a novel method and apparatus for testing TSVs within a semiconductor device. According to embodiments illustrated and described in the disclosure, a TSV may be tested by stimulating and measuring a response from a first end of a TSV while the second end of the TSV held at ground potential. Multiple TSVs within the semiconductor device may be tested in parallel to reduce the TSV testing time according to the disclosure.

Disclosed is a test circuit for testing an integrated circuit core or an external circuit of the integrated circuit core. The test circuit may not only transmit a cell function input to a cell function output using only one multiplexer in a bypass mode, may but also use a clock gating scheme capable of blocking a clock signal from transmitting to a scan flip-flop to hold a capture procedure.

An integrated circuit (IC) can include a plurality of circuit blocks, wherein each circuit block includes design for testability (DFT) circuitry. The DFT circuitry can include a scan interface, wherein each scan interface is uniform with the scan interface of each other circuit block of the plurality of circuit blocks, an embedded deterministic test circuit coupled to the scan interface, wherein the embedded deterministic test circuit couples to circuitry under test, and a scan response analyzer coupled to the scan interface. The scan response analyzer is configured to operate in a selected scan response capture mode selected from a plurality of scan response capture modes. The IC can include a global scan router connected to the scan interfaces of the plurality of circuit blocks. The global scan router is configured to activate a subset of the plurality of circuit blocks in parallel for a scan test.

The disclosure describes a novel method and apparatus for improving interposers that connected stacked die assemblies to system substrates. The improvement includes the addition of IEEE 1149.1 circuitry within interposers to allow simplifying interconnect testing of digital and analog signal connections between the interposer and system substrate it is attached too. The improvement also includes the additional 1149.1 controlled circuitry that allows real time monitoring of voltage supply and ground buses in the interposer. The improvement also includes the additional of 1149.1 controlled circuitry that allows real time monitoring of functional digital and analog input and output signals in the interposer. The improvement also provides the ability to selectively serially link the 1149.1 circuitry in the interposer with 1149.1 circuitry in the die of the stack.

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 multi-die integrated circuit uses an on-chip test distribution module to distribute test data to different dies, such as processor chiplets. The test distribution module receives test input data from an external source via one or more integrated circuit pins and distributes the test input data to the different dies, such that the different dies are able to concurrently apply the test data to one or more circuits. Based on application of the test input data the different dies concurrently generate corresponding test results that are used to identify and address design or operation errors at the dies.