A system includes a test access port (TAP) configured to provide internal joint test action group (IJTAG) access to one or more test data registry (TDR). The system further includes a plurality of hierarchical electronic components, wherein each hierarchical electronic component includes a de-asserted segment inserted bit (D-SIB) register, an asserted segment inserted bit (A-SIB) register, and a TDR associated with the D-SIB register. Each D-SIB register is configured to prevent access to its associated TDR when a reset signal is asserted and each A-SIB register is configured to provide access to its subsequent A-SIB register or D-SIB register coupled thereto when the reset signal is asserted.

The disclosure describes a process and apparatus for accessing devices on a substrate. The substrate may include only full pin JTAG devices (504), only reduced pin JTAG devices (506), or a mixture of both full pin and reduced pin JTAG devices. The access is accomplished using a single interface (502) between the substrate (408) and a JTAG controller (404). The access interface may be a wired interface or a wireless interface and may be used for JTAG based device testing, debugging, programming, or other type of JTAG based operation.

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.

An error diagnosis circuit includes a signal input for connection to a communication interface, configured to receive a first instruction and a second instruction for a device. A circuit is configured to compare the first instruction and the second instruction and to output an error signal if the first instruction and the second instruction differ from one another.

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.

According to an embodiment of the present invention, a computer-implemented method for testing a microelectronic chip is described. The method may include dividing, via a processor running a scanning engine, a plurality of sections of the microelectronic chip. Each of the plurality of sections includes at least two latch sets in at least one scan chain. The method may further include determining, via the processor, based on the dividing, whether each of the plurality of sections fail a data test. The determining comprises interleaving the plurality of sections by scanning, via the processor, an alternating latch set from each scan chain in a first section, and scanning an alternating latch set from each scan chain in a second section.

A falling edge controller includes a controller having an inverted TCK (Test Clock) input, a TMS (Test Mode Select) input, a shift register control output, an update register control output, and a shift output; a shift register having a TDI (Test Data In) input, a shift register control input coupled to the shift register control output, address inputs, a select input, address and select outputs, and a TDO (Test Data Out) output; an update register having address and select inputs coupled to the address and select outputs, an update register control input coupled to the update register control output, address outputs coupled to the address inputs, and a select output coupled to the select input; and address circuitry having address inputs coupled to the address outputs, and having an enable output.

Described herein are integrated circuit chips having test circuitry designed such that independently selectable testing of different power domains using a same scan chain compressor-decompressor circuit may be performed. Also disclosed herein are integrated circuit chips having test circuitry designed such that independently selectable testing of different power domains using multiple different scan chain compressor-decompressor circuits may be performed.