Abstract: An integrated circuit or circuit board includes functional circuitry and a scan path. The scan path includes a test data input lead, a test data output lead, a multiplexer, and scan cells. A dedicated scan cell has a functional data output separate from a test data output. Shared scan cells each have a combined output for functional data and test data. The shared scan cells are coupled in series. The test data input of the first shared scan cell is connected to the test data output of the dedicated scan cell. The combined output of one shared scan cell is coupled to the test data input lead of another shared scan cell. The multiplexer has an input coupled to the test data output, an input connected to the combined output lead of the last shared scan cell in the series, and an output connected in the scan path.

Abstract: An interface device is adapted to: in a first mode, in reaction to test signals and corresponding to a test standard, output signals corresponding to the test standard via at least one signal line. In a second mode it is adapted to, in reaction to test signals and corresponding to the test standard, output signals that do not correspond to the test standard via the at least one signal line.

Abstract: A BSC macrostructure for three-dimensional wiring includes a BSC (boundary scan cell) and an aperture electrode for electrode connection which is connected to the BSC.

Abstract: 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.

Abstract: An integrated circuit is described that includes a stored program processor for test and debug of user-definable logic plus external interface between the test/debug circuits and the component pins. The external interface may be via an existing test interface or a separate serial or parallel port. Test and debug circuits may contain scan strings that may be used to observe states in user-definable logic or be used to provide pseudo-random bit sequences to user-definable logic. Test and debug circuits may also contain an on-chip logic analyzer for capturing sequences of logic states in user-definable circuits. Test and debug circuits may be designed to observe states in user-definable circuits during the normal system operation of said user-definable circuits.

Abstract: Scan distributor, collector, and controller circuitry connect to the functional inputs and outputs of core circuitry on integrated circuits to provide testing through those functional inputs and outputs. Multiplexer and demultiplexer circuits select between the scan circuitry and the functional inputs and outputs. The core circuitry can also be provided with built-in scan distributor, collector, and controller circuitry to avoid having to add it external of the core circuitry. With appropriately placed built-in scan distributor and collector circuits, connecting together the functional inputs and outputs of the core circuitry also connects together the scan distributor and collector circuitry in each core. This can provide a hierarchy of scan circuitry and reduce the need for separate test interconnects and multiplexers.

Abstract: An address and command port interface selectively enables JTAG TAP domain operations and Trace domain operations within an IC. The port carries TMS and TDI input and TDO output on a single pin and receives a clock signal on a separate pin. The addressable two pin interface loads and updates instructions and data to the TAP domain within the IC. The instruction or data update operations in multiple ICs occur simultaneously. A process transmits data from an addressed target device to a controller using data frames, each data frame comprising a header bit and data bits. The logic level of the header bit is used to start, continue, and stop the data transmission to the controller. A data and clock signal interface between a controller and multiple target devices provides for each target device to be individually addressed and commanded to perform a JTAG or Trace operation.

Abstract: An error-correction code is generated on a line-by-line basis of the physical logic register and latch contents that store encoded words within a processor just before the processor is put into sleep mode, and later-generated syndrome bits are checked for any soft errors when the processor wakes back up, e.g., as part of the power-up sequence.

Abstract: An integrated circuit can have plural core circuits, each having a test access port that is defined in IEEE standard 1149.1. Access to and control of these ports is though a test linking module. The test access ports on an integrated circuit can be arranged in a hierarchy with one test linking module controlling access to plural secondary test linking modules and test access ports. Each secondary test linking module in turn can also control access to tertiary test linking modules and test access ports. The test linking modules can also be used for emulation.

Abstract: The present disclosure describes novel methods and apparatuses for directly accessing JTAG Tap domains that exist in a scan path of many serially connected JTAG Tap domains. Direct scan access to a selected Tap domain by a JTAG controller is achieved using auxiliary digital or analog terminals associated with the Tap domain and connected to the JTAG controller. During direct scan access, the auxiliary digital or analog terminals serve as serial data input and serial data output paths between the selected Tap domain and the JTAG controller.

Abstract: An integrated circuit containing memory includes IEEE 1149.1 (JTAG) controlled self-repair system that permits permanent repair of the memory after the integrated circuit has been packaged. The JTAG controlled self-repair system allows a user to direct circuitry to blow fuses using an externally supplied voltage to electrically couple or isolate components to permanently repair a memory location with JTAG standard TMS and TCK signals. The system may optionally sequentially repair more than one memory location using a repair sequencer.

Abstract: A test driver transmitter drives a test signal through a resistive termination circuit to a first pin to test components on a board during a boundary scan test operation. A test receiver receives the test signal through a second pin and a pass gate coupled to the second pin during the boundary scan test operation. A test signal is transmitted to the test receiver during loopback operation through a loopback circuit.

Abstract: The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

Abstract: An electronic device comprises a processing stage, a JTAG port including a test data input pin (TDI), a test data output pin (TDO), a test mode select pin (TMS), a test clock pin (TCK), and a test access port (TAP) controller having a data register (DR) shift state and an instruction register shift (IR) state. The electronic device operates in a scan event mode automatically mapped an incoming event to the TDO pin.

Abstract: Various methods and apparatuses are described for a system that includes some on-chip components, e.g., I-Os, test processors, soft wrappers, etc., an external testing unit that provides Parametric Measurement Unit (PMU) capability, and various tests performed on the I-Os by the on-chip testing logic, the test vector patterns supplied by the external testing unit.

Abstract: 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.

Abstract: The disclosure describes a novel method and apparatus for providing expected data, mask data, and control signals to scan test architectures within a device using the falling edge of a test/scan clock. The signals are provided on device leads that are also used to provide signals to scan test architectures using the rising edge of the test/scan clock. According to the disclosure, device test leads serve to input different test signals on the rising and falling edge of the test/scan clock which reduces the number of interconnects between a tester and the device under test.

Abstract: Fault tolerant programming of a programmable device advantageously occurs via a host controller that first queries the programmable device through a Boundary scan interface to identify the device. Thereafter, host controller selects a program file in accordance with the device identity for subsequent downloading via the Boundary scan interface to program the device. Thereafter, the host controller verifies that successful programming has occurred.

Abstract: A method comprises performing at least one zero-bit scan across an interface link. The at least one zero-bit scan defines a command window. The method further comprises an interface adapter counting a number of inert scans in the command window, and the number of inert scans defines a particular command or data. An inert scan results in no data being moved into or out of the interface adapter.

Abstract: A method, a system, and a processor for loading a logical device online are disclosed. The method for loading a logical device online includes receiving an online loading command; disabling a Joint Test Action Group (JTAG) link of a board on which the logical device is located through a bus between a processor and the logical device according to the online loading command, and enabling a link between an input/output (I/O) interface and a JTAG interface of the logical device through the bus according to the online loading command; and controlling the logical device through the bus so that the logical device is loaded online through the link between the I/O interface and the JTAG interface of the logical device. In this way, the logical device is loaded online without occupying any I/O interface or requiring addition of any I/O device.

Abstract: An integrated circuit carries an intellectual property core. The intellectual property core includes a test access port 39 with test data input leads 15, test data output leads 13, control leads 17 and an external register present, ERP lead 37. A scan register 25 encompasses the intellectual property core and ERP lead 37 carries a signal indicating the presence of the scan register.

Abstract: Apparatus and other embodiments associated with a distributed Joint Test Access Group (JTAG) test bus controller (TBC) architecture are described. One example method includes providing first on-board scan programming (OSP) data to a first circuit board configured with a first TBC and located in a computer. The example method also includes providing second OSP data to a second circuit board configured with a second test bus controller and located in the same computer. The example method also includes controlling OSP to be performed at least partially in parallel on the first circuit board and the second circuit board.

Abstract: A test controller implemented in an integrated circuit (IC) with partitioned scan chains provides enhanced control in performing scan tests. According to an aspect, a test controller can selectively control scan-in, scan-out and capture phases of scan tests for different scan chains of the IC to be independent. The number of pins required to interface the test controller with an external tester is less than the number of partitions that the test controller can support. According to another aspect, an IC includes a register corresponding to each partition to support transition fault (or LOS) testing. According to another aspect, an IC with partitioned scan chains includes serial to parallel and parallel to serial converters, thereby minimizing the external pins required to support scan tests.

Abstract: The disclosure describes a novel method and apparatus for providing a shadow access port within a device. The shadow access port is accessed to perform operations in the device by reusing the TDI, TMS, TCK and TDO signals that are used to operate a test access port within the device. The presence and operation of the shadow access port is transparent to the presence and operation of the test access port. According to the disclosure, the shadow access port operates on the falling edge of the TCK signal while the test access port conventionally operates on the rising edge of the TCK signal.

Abstract: This disclosure describes a reduced pin bus that can be used on integrated circuits or embedded cores within integrated circuits. The bus may be used for serial access to circuits where the availability of pins on ICs or terminals on cores is limited. The bus may be used for a variety of serial communication operations such as, but not limited to, serial communication related test, emulation, debug, and/or trace operations of an IC or core design. Other aspects of the disclosure include the use of reduced pin buses for emulation, debug, and trace operations and for functional operations. In a fifth aspect of the present disclosure, an interface select circuit, FIGS. 41-49, provides for selectively using either the 5 signal interface of FIG. 41 or the 3 signal interface of FIG. 8.

Abstract: An IC includes an IEEE 1149.1 standard test access port (TAP) interface and an additional Off-Chip TAP interface. The Off-Chip TAP interface connects to the TAP of another IC. The Off Chip TAP interface can be selected by a TAP Linking Module on the IC.

Abstract: A position-based scheduling capability supports interaction between one or more user applications and a scheduler for performing testing via a scan chain of a unit under test. The scheduler receives access requests from one or more user applications, where each access request is a request for access to a segment of the scan chain, respectively. The scheduler determines scheduling of the access requests using a circuit model configured to represent an ordering of the segments of the scan chain. The scheduler may provide the access responses to the user application(s) from which the access requests are received, thereby enabling the user application(s) to issue test operations toward a processor configured to generate test data to be applied to the scan chain. The scheduler may obtain the test operations and send the test operations toward a processor configured to generate test data to be applied to the scan chain.

Abstract: A multi-chip test system and a method thereof utilize a Complex Programmable Logic Device (CPLD) to be connected in series to multiple chips having a Joint Test Action Group (JTAG) interface for function inspection. The test system includes a device to-be-tested and a control device. The device to-be-tested includes multiple chips, a CPLD, and a second JTAG interface. Each of the chips has a first JTAG interface. The CPLD is coupled to the chips through the first JTAG interfaces. The second JTAG interface is connected to the CPLD. The control device is connected to the second JTAG interface and used for sending a switching instruction to the CPLD. In the test method, firstly, a switching instruction is received to select a chip to-be-tested; then, a test signal is sent to the chip to-be-tested according to the chip to-be-tested; and the chip to-be-tested transfers a test result back to a CPLD according to the test signal.

Abstract: An integrated circuit or circuit board includes functional circuitry and a scan path. The scan path includes a test data input lead, a test data output lead, a multiplexer, and scan cells. A dedicated scan cell has a functional data output separate from a test data output. Shared scan cells each have a combined output for functional data and test data. The shared scan cells are coupled in series. The test data input of the first shared scan cell is connected to the test data output of the dedicated scan cell. The combined output of one shared scan cell is coupled to the test data input lead of another shared scan cell. The multiplexer has an input coupled to the test data output, an input connected to the combined output lead of the last shared scan cell in the series, and an output connected in the scan path.

Abstract: The present disclosure describes a novel method and apparatus of using the JTAG TAP's TMS and TCK terminals as a general purpose serial Input/Output (I/O) bus. According to the present disclosure, the TAP's TMS terminal is used as a clock signal and the TCK terminal is used as a bidirectional data signal to allow serial communication to occur between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC.

Abstract: The disclosure describes novel methods and apparatuses for accessing test compression architectures (TCA) in a device using either a parallel or serial access technique. The serial access technique may be controlled by a device tester or by a JTAG controller. Further the disclosure provides an approach to access the TCA of a device when the device exists in a daisy-chain arrangement with other devices, such as in a customer's system. Additional embodiments are also provided and described in the disclosure.

Abstract: The present disclosure describes novel methods and apparatuses for directly accessing JTAG Tap domains that exist in a scan path of many serially connected JTAG Tap domains. Direct scan access to a selected Tap domain by a JTAG controller is achieved using auxiliary digital or analog terminals associated with the Tap domain and connected to the JTAG controller. During direct scan access, the auxiliary digital or analog terminals serve as serial data input and serial data output paths between the selected Tap domain and the JTAG controller.

Abstract: Today many instances of IEEE 1149.1 Tap domains are included in integrated circuits (ICs). While all TAP domains may be serially connected on a scan path that is accessible external to the IC, it is generally preferred to have selectivity on which Tap domain or Tap domains are accessed. Therefore Tap domain selection circuitry may be included in ICs and placed in the scan path along with the Tap domains. Ideally, the Tap domain selection circuitry should only be present in the scan path when it is necessary to modify which Tap domains are selected in the scan path. The present disclosure describes a novel method and apparatus which allows the Tap domain selection circuitry to be removed from the scan path after it has been used to select Tap domains and to be replaced back into the scan path when it is necessary to select different Tap domains.

Abstract: A semiconductor device and a method for driving the same rapidly detect failure of a through-semiconductor-chip via and effectively repairing the failure using a latching unit assigned to each through-semiconductor-chip via. The semiconductor device includes a plurality of semiconductor chips that are stacked, and a plurality of through-semiconductor-chip vias to commonly transfer a signal to the plurality of semiconductor chips, wherein each of the semiconductor chips includes a multiplicity of latching units assigned to the through-semiconductor-chip vias and the multiplicity of latching units of each of the semiconductor chips constructs a boundary scan path including the plurality of through-semiconductor-chip vias to sequentially transfer test data.

Abstract: A TAP linking module (21, 51) permits plural TAPs (TAPs 1-4) to be controlled and accessed from a test bus (13) via a single TAP interface (20).

Abstract: A TAP linking module (21, 51) permits plural TAPs (TAPs 1-4) to be controlled and accessed from a test bus (13) via a single TAP interface (20).

Abstract: This disclosure describes different ways to improve the operation of a device's 1149.1 TAP to where the TAP can perform at-speed Update & Capture, Shift & Capture and Back to Back Capture & Shift operations. In a first embodiment of the disclosure the at-speed operations are achieved by time division multiplexing CMD signals onto the TMS input to the TAP. The CMD signals are input to a CMD circuit that operates in conjunction with a Dual Port Router to execute the at-speed operations of a circuit. In a second embodiment of the disclosure the at-speed operations are achieved by detecting the TAP's Exit1DR state as a CMD signal that is input to the CMD circuit that operates in conjunction with a Dual Port Router to execute the at-speed operations of a circuit.

Abstract: A method and apparatus for implementing integrated circuit security features are provided to selectively disable testability features on an integrated circuit chip. A test disable logic circuit receives a test enable signal and responsive to the test enable signal set for a test mode, establishes a test mode and disables ASIC signals. Responsive to the test enable signal not being set, the ASIC signals are enabled for a functional mode and the testability features on the integrated circuit chip are disabled. When the functional mode is enabled, the test disable logic circuit prevents the test mode from being established while the integrated circuit chip is powered up.

Abstract: The disclosure provides a novel method and apparatus for inputting addresses to devices to select the device TAP for access. Further, the disclosure provides a novel method and apparatus for inputting addresses for selecting device TAPs and for inputting commands for commanding circuitry within the device. The inputting of addresses or the inputting of addresses and commands is initiated by a control bit input on TDI that is recognized during the Run Test/Idle, Pause-DR or Pause-IR TAP states.

Abstract: In a first embodiment a TAP of IEEE standard 1149.1 is allowed to commandeer control from a WSP 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. One approach provides for the TAP to maintain access and control of the TAP instruction register, but provides for a selected data register to be accessed and controlled by either the TAP+ATC or by the discrete CaptureDR, UpdateDR, TransferDR, ShiftDR, and ClockDR WSP data register control signals.

Abstract: A method for designing an integrated circuit is disclosed. The method generally comprises the steps of (A) splitting a design layout of the integrated circuit into a plurality of tiles, (B) adding a plurality of tie-to cells to the design layout, wherein at least one of the tie-to cells generating a tie-to signal at a particular logical level is added into each of the tiles having at least one gate with an input fixed to the particular logical level and (C) routing the tie-to signal to each of the inputs within each of the tiles.

Abstract: Connection circuitry couples scan test port (STP) circuitry to test access port (TAP) circuitry. The connection circuitry has inputs connected to scan circuitry control output leads from the TAP circuitry, a select input lead, and a clock input lead. The connection circuitry has outputs connected to a scan enable (SE) input lead, a capture select (CS) input lead, and the scan clock (CK) input lead of the STP circuitry. The connection circuitry includes a multiplexer having a control input connected with a clock select lead from the TAP circuitry, an input connected with a functional clock lead, an input connected with the clock input lead, an input connected with a Clock-DR lead from the TAP circuitry, an OFF lead, and an output connected with the scan clock input lead.

Abstract: A latch circuit includes a first latch that stores data provided from a data input terminal when a clock is provided from a clock input terminal, and stores scan data provided from a scan data input terminal when a first scan clock is provided from a first scan clock input terminal, a logical circuit that performs a logical operation for a second scan clock provided from the second scan clock input terminal and for an operational mode signal provided from the operation mode input terminal, and generates an update clock and a second latch including an update input terminal connected to an output terminal of the first latch, and an update clock input terminal connected to an output terminal of the logical circuit, the second latch holds the data or the scan data provided from the update input terminal when the update clock is provided.

Abstract: An integrated circuit comprising (i) a plurality of portions, each portion including test control circuitry; and (ii) at least one test input arranged to receive test signals, the circuit having a test mode in which one or more of the plurality of portions are testable, wherein the circuit has a reset mode which has priority over the test mode.

Abstract: An integrated circuit and method for testing memory on the integrated circuit are provided. The integrated circuit has processing logic for performing data processing operations on data, and a plurality of memory units for storing data for access by the processing logic. Further, memory test logic is provided to perform a sequence of tests in order to seek to detect memory defects in the memory units. The memory test logic comprises a plurality of test wrapper units, each test wrapper unit associated with one of the memory units and being operable to execute tests on the associated memory unit, and a test controller for controlling performance of the sequence of tests by communicating with each of the test wrapper units to provide test data defining each test to be executed by that test wrapper unit.

Abstract: A circuit includes a control flip-flop inputting a scan control signal and a scan path chain formed of scan storage elements serially connected. The scan path chain performs a shift operation as a first mode when the control flip-flop outputs a first status value, and performs a normal operation as a second mode when the control flip-flop outputs a second status value. When the scan control signal is switched from the first status value to the second status value, the control flip-flop outputs the second status value to the scan storage elements in synchronization with a first clock pulse, after the switching, of a clock provided to the scan storage elements. When the scan control signal is switched from the second status value to the first status value, the control flip-flop outputs the first status value to the scan storage elements at a timing of the scan control signal switching.

Abstract: A test system includes a computer and an interface device for accessing a scan chain on an application specific integrated circuit (ASIC) under test. The computer includes a memory that contains application software that when executed by the computer quantifies soft errors and soft error rates (SER) in storage elements on the ASIC. The interface device receives commands and data from the computer, translates the commands and data from a first protocol to a second protocol and communicates the commands and data in the second protocol to the ASIC. A method for measuring SER in the ASIC includes baseline, comparison, and latch up accesses of data in a scan chain in the ASIC. Between accesses, the ASIC is exposed to a neutron flux that accelerates the occurrence of soft errors due to ionizing radiation upon the ASIC.

Abstract: A semiconductor integrated circuit device includes a first clock domain having a plurality of first flip-flops which is configured to operate with a high-speed clock; a second clock domain having a plurality of second flip-flops, composed of a third flip-flop and a plurality of fourth flip-flops, which is configured to operate with a low-speed clock; and a test clock supplying section configured to supply, at a time of delay fault test for the second clock domain, a test clock based on the high-speed clock to the third flip-flop to which data from the first clock domain is input, and not to supply the test clock to the plurality of fourth flip-flops.

Abstract: This disclosure describes a reduced pin bus that can be used on integrated circuits or embedded cores within integrated circuits. The bus may be used for serial access to circuits where the availability of pins on ICs or terminals on cores is limited. The bus may be used for a variety of serial communication operations such as, but not limited to, serial communication related test, emulation, debug, and/or trace operations of an IC or core design. Other aspects of the disclosure include the use of reduced pin buses for emulation, debug, and trace operations and for functional operations. In a fifth aspect of the present disclosure, an interface select circuit, FIGS. 41-49, provides for selectively using either the 5 signal interface of FIG. 41 or the 3 signal interface of FIG. 8.

Abstract: A TAP linking module (21, 51) permits plural TAPs (TAPs 1-4) to be controlled and accessed from a test bus (13) via a single TAP interface (20).