Abstract: A semiconductor device with test interface, as well as to a method for operating a semiconductor device is disclosed. In one embodiment, in a test operating mode, the semiconductor device is, via a first pin, supplied with a work cycle signal synchronized with a test environment and, via at least one second pin, with test data. In accordance with a first embodiment it is suggested, so as to reduce the number of pins, that the work cycle signal is simultaneously used as test data clock signal.

Abstract: In one aspect, a data transmission rate of a message signal representing a bus message at a bus and a propagation delay between an occurrence of the message signal at a transmission output to the bus and an occurrence of the message signal at a receive input from the bus are determined. Bit error detection is selectively disabled responsive to a compatibility between the data transmission rate and the propagation delay. In another aspect, a bus line interface includes a transmit output and a receive input coupled to a bus line, a bit error detection module and a data rate module. The bus line interface also includes a bit error control module to selectively disable the bit error detection module based on a propagation delay between a signal and a reflected signal and based on a data transmission rate of the signal.

Abstract: The present test apparatus avoids proximity restriction violation of an edge and surely generates a test signal. There is provided a test apparatus that tests a device under test. The test apparatus includes a test pattern generating section that generates a test pattern to test the device under test every test period, a plurality of edge generators that respectively generate an edge of a test signal to be supplied to the device under test based on the test pattern every cycle period of a reference clock that is used as a reference for an operation of this test apparatus, a selecting section that selects which edge generator generates each edge of a test signal to be output during the next cycle period based on a pattern of the edge generated during the current cycle period, and a test signal supplying section that supplies the test signal according to each edge generated from the selected edge generator to the device under test.

Abstract: Systems and methods for performing logic built-in-self-tests (LBISTs) where data comparisons are performed in the MISR. In one embodiment, a STUMPS-type LBIST architecture includes scan chains interposed between portions of the functional logic of the logic circuit. Test bit patterns are scanned into the scan chains, propagated through the functional logic, and captured in scan chains following the functional logic. The bits are scanned out of the scan chains into a self-compare MISR that creates a signature from the computed bit patterns and then compares the signature of the computed bit patterns with an expected signature, giving a pass/fail result. This single bit result reduces the bandwidth required to communicate the result(s) of the LBIST testing to the test equipment. As a result, a larger number of devices can be tested by a given piece of test equipment.

Abstract: A pipelined data processing system includes functional circuitry having a plurality of test points located at predetermined circuit nodes within the functional circuitry, at least one staging storage element associated with a pipeline stage of the data processing system which is coupled to receive test data directly from the plurality of test points, and a multiple input shift register (MISR) coupled to receive test data from the at least one staging storage element and provide a MISR result. In one aspect, the at least on staging storage element has a plurality of staging storage elements wherein each of the plurality of staging storage elements corresponds to a different pipeline stage of the data processing system. In another aspect the MISR result is independent of varying memory access times.

Abstract: A method and apparatus for determining the characteristics of a communications channel within a high speed memory system includes generating a first signal having a known and repeating pattern and generating a second signal having a pseudo-random pattern. The first and second signals are combined to produce a combined signal. The combined signal is transmitted over a communications channel of a memory system and received by the memory devices of the memory system. Each memory device removes the second signal from the received combined signal to produce a received first signal. Parameters associated with transmitting and receiving may be adjusted by examining the pattern of the received first signal to determine if it has the known pattern of the first signal. Because of the rules governing abstracts, this abstract should not be used to construe the claims.

Abstract: An apparatus for testing an IC device includes a test signal generator for generating a predefined sequence of test signals that are input to the IC device. A timing skew monitor is provided for monitoring the test signals input in the IC device and a signal output from the IC device for a predetermined time period, and creating an array indicating an execution or a nonexecution of signal timing combinations of one of the test signals relative to at least one of the other test signals within the predetermined time period by the IC device. A determination as to whether the desired signal timing combinations of the test signals have been executed by the IC device is made by an operator.

Abstract: A system for validating data collected in a first clock domain. A performance counter is disposed in a second clock domain to perform performance computations relative to the data. Validation circuitry is in communication with the data in order to provide to the performance counter a validation signal indicative of the validity of the data.

Abstract: The methods and circuits of the present invention relate to testing integrated circuits. According to one aspect of the invention, a method of testing an integrated circuit is disclosed. The method comprises the steps of coupling test equipment to the integrated circuit; coupling a test equipment clock signal from the test equipment to the integrated circuit, wherein the test equipment clock signal has a first frequency; generating an internal burst clock signal within the integrated circuit based upon the test equipment clock signal, wherein the internal test clock signal has a burst frequency; and testing the integrated circuit using the internal burst clock signal. Other methods and circuits for testing programmable logic devices are also described.

Abstract: Two delay chains having in each case n series-connected unidirectional delay elements are provided for controllably delaying electrical signals between a circuit input and at least one circuit output. Each delay element is an active circuit with a fixed transit time. The input of the first delay element of the first chain is connected to the circuit input and the output of each delay element of the first delay chain is selectively connectable to the input of the (n?i+1)th delay element of the second delay chain via a respectively associated switch of a first group of switches, wherein i=1 . . . n is the ordinal number of the delay elements of the first delay chain. The output of the last delay element of the second chain is connected as a circuit output.

Abstract: Methods and structures utilizing multiple configuration bitstreams to program integrated circuits (ICs) such as programmable logic devices, thereby enabling the utilization of partially defective ICs. A user design is implemented two or more times, preferably utilizing different programmable resources as much as possible in each configuration bitstream. The resulting user configuration bitstreams are stored along with associated test bitstreams in a memory device, e.g., a programmable read-only memory (PROM). Under the control of a configuration control circuit or device, the test bitstreams are loaded into a partially defective IC and tested using an automated testing procedure. When a test bitstream is found that enables the associated user design to function correctly in the programmed IC, i.e.

Abstract: An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are caculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: One embodiment disclosed relates to a method of compiling a program to be executed on a target central processing unit (CPU). The method includes opportunistically scheduling diagnostic testing of CPU registers. The method may include use of a predetermined level of aggressiveness for the scheduling of the register diagnostic testing. The scheduled diagnostic testing may include writing known data to a register, reading data from the register, and comparing the known data with the data that was read. If the comparison indicates a difference, then a jump may occur to a fault handler routine.

Abstract: A semiconductor integrated circuit comprises a combinational circuit section having a combinational circuit, a scan path circuit for inputting and outputting a value from and to the combinational circuit section in accordance with a scan enable signal and in synchronization with a clock signal, and a clock control section for generating and outputting a predetermined number of pulses as the clock signal after a predetermined period has passed since a time when an output command signal was received. The clock control section has an oscillator circuit for generating and outputting the pulse, and is configured to output a last pulse of the predetermined number of pulses in a manner which holds a logical value immediately after an active edge for the scan path circuit.

Abstract: A method for enabling bitwise or bit slice constraints to be provided as part of the test generation process, by providing a language structure which enables these constraints to be expressed in a test generation language such as e code for example. The language structure for such bitwise constraints is then handled in a more flexible manner, such that the test generation process does not attempt to rigidly “solve” the expression containing the constraint as a function. Therefore, the propagation of constraints in such a structure do not necessarily need to be propagated from left to right, but instead are generated in a multi-directional manner. The language structure is particularly suitable for such operators as “[: ]”, “|”, “&”, “^”, “˜”, “>>” and “<<”.

Abstract: There is provided a semiconductor test apparatus which uses a test processor to apply a test signal to a DUT having a semiconductor device within it to determine whether the memory is acceptable or not on the basis of a response signal, and uses a repair analysis computing unit to analyze the result of the test to determine how to replace a defective cell of the memory with a spare line. The repair analysis computing unit includes a fail memory which stores test results and a general-purpose repair analysis part which analyzes the test results in accordance with an MRA program and inserts and executes a user function of a user analysis program between units of analysis processing.

Abstract: Methods of operating an apparatus allow a memory to generate a test mode signal to trigger a test, in response to the memory detecting a predetermined command from a system bus.

Abstract: An in-system memory testing method includes transparently selecting and “stealing” a portion of memory from the memory system for running memory tests, then running one or more of the numerous known memory system tests on the selected portion of memory, and then inserting the selected, and now tested, portion of memory back into the system for normal application use. The disclosed in-system memory testing method is capable of testing system memory in both offline and online environments, without imposing any additional hardware requirements or significantly affecting system performance. The disclosed in-system memory testing method is compatible with any conventional prior art functional test algorithm for in-system memory testing and can be performed under real life system environmental conditions. Therefore, the disclosed in-system memory testing method complements other test techniques like BIST/POST that are conventionally used only at the time of system boot up.

Abstract: An application specific integrated circuit (ASIC) uses a dedicated interface between core logic and an independent Serializer/De-serializer bus (SBus) to provide SBus capabilities to the core logic. In addition to the dedicated interface, the ASIC includes a controller responsive to a set of signals and a plurality of receivers distributed about the SBus. Each of the receivers is responsive to a set of commands that can be reused to test logic and support functions across each revision of the ASIC as well as to test separate ASICs with similar arrangements of support functions without requiring the generation of a distinct scan vector to test the ASIC. Additional interfaces, such as an I.E.E.E. 1149.1 interface, further extend SBus capabilities to external test equipment.

Abstract: Read the description file of a PCBA without determining and selecting connectors which might be relevant to boundary scan. The description file of the PCBA determines which pins of the connectors on the PCBA should correspond to the pins of a test I/O module. And use the wiring report generated by an auto test program generator to correspond the pins of the test I/O module to the pins of the connectors which are accessed by boundary scan. Thus the IC of the test I/O module would not have any unused pin between any two consecutive pins wired to the connectors of the PCBA.