Abstract: A test method for a semiconductor device that is provided with an ECC circuit that uses product code that is composed of a first code and a second code for implementing error correction of a memory, the test method includes steps of: obtaining first pass/fail determination results and second pass/fail determination results that are realized by independent correction operations based on the first code and the second code, respectively; recording the results in a first fail memory and a second fail memory, respectively; executing a prescribed logical operation such as an AND operation relating to the contents of the first fail memory and the contents of the second fail memory; and based on the results of the logical operation, remedying both fail bits and potential fail bits.

Abstract: Systems and methods are disclosed to detect and correct errors in a flash memory using an error correction cache that provides error correction information by accessing data from a physical block number (PBN) of the flash memory; and if a data error occurred, applying error correction information stored in the cache corresponding to the accessed PBN to correct the data error.

Abstract: A system and method for determining data integrity as such data passes through a FIFO. A generator is provided for appending a bit in a predetermined bit location in each packet pushed into the FIFO in response clock signals. The appended bit is a function of the information pushed into the FIFO. A checker is provided for providing an indication of the information integrity in response to bits produced at an output of the FIFO in the predetermined bit location. In one embodiment, the generator is a parity generator and the checker is a parity checker. In one embodiment, during an initial test mode, one parity type is introduced into the FIFO by the parity generator and the opposite parity type is checked at the output of the FIFO by the parity checker to determine whether the parity checker is able to produce parity error signals. In another embodiment, the generator is a packet delimiter generator and the checker is a packet delimiter checker.

Abstract: A method is for refreshing a dynamic random access memory coupled to an error correction system, which uses an error correcting code. The dynamic random access memory includes groups of memory cells storing bits, each group of memory cells being subdivided into packets of memory cells. Each packet of memory cells is supplemented with the error correcting code. The method includes performing a retention test on each group of memory cells, and increasing a memory refresh frequency if a number of test groups of memory cells having at least one erroneous packet is greater than a threshold.

Abstract: A memory system is provided which comprises a main memory that stores main data and reference data; a first storage that stores the reference data; and a controller that accesses the reference data from the main memory upon receipt of a power up signal, and loads the main data into a second storage when the reference data retrieved from the main memory is tested to be the same as the reference data in the first storage.

Abstract: A memory device capable of detecting its failure, the memory device includes a data input section for receiving data applied from an external part of the memory device; a latch section for receiving and storing therein the data which have passed through the data input section; memory cell arrays for storing therein the data which have passed through the data input section; and a data compressor for determining whether or not the data stored in the latch section and the data stored in the memory cell arrays are identical to each other.

Abstract: A normal write data selection circuit operates in the normal operation mode, and thus outputs data received through external data terminals to any one of regular cell arrays selected according to an address. A test write control circuit operates in the test mode, and thus writes test data into a regular memory cell at a location corresponding to a location of a parity memory cell into which test parity data are written in each of regular cell arrays. Therefore, since a common test pattern can be used to test both the regular memory cell and the parity memory cell, test cost can be curtailed.

Abstract: A technique for testing a memory array. More particularly, embodiments of the invention relate to a memory array testing architecture in which a memory array within a device under test (DUT) is able to be tested at speeds substantially similar to those under typical operating conditions of the memory array without incurring significant die real estate and power penalties.

Abstract: A method and apparatus to correctly compute a vector-gather, vector-operate (e.g., vector add), and vector-scatter sequence, particularly when elements of the vector may be redundantly presented, as with indirectly addressed vector operations. For an add operation, one vector register is loaded with the “add-in” values, and another vector register is loaded with address values of “add to” elements to be gathered from memory into a third vector register. If the vector of address values has a plurality of elements that point to the same memory address, the algorithm should add all the “add in” values from elements corresponding to the elements having the duplicated addresses. An indirectly addressed load performs the “gather” operation to load the “add to” values. A vector add operation then adds corresponding elements from the “add in” vector to the “add to” vector. An indirectly addressed store then performs the “scatter” operation to store the results.

Abstract: A memory cell test circuit for use in a semiconductor memory device having a plurality of banks connected to a plurality of global input/output lines, including: a plurality of bank switching units for transferring data outputted from the plurality of banks to the plurality of global input/output lines based on a test mode signal and a plurality of control clock signals; a logic operation unit for performing a logic operation to the data outputted to the plurality of global input/output lines and for outputting a result of the logic operation to a test global input/output line; and a switching unit coupled to the test global input/output line and the plurality of global input/output lines for selectively passing data of the test global input/output line and data of the global input/output lines based on the test mode signal and the plurality of control clock signals.

Abstract: An RRAM design having linear BIST memory and rectangular BIST memory, the improvement comprising at least one of the linear BIST memory and the rectangular BIST memory formed only of flipflops and logic cells.

Abstract: A memory test system can screen objects of tests accurately at low cost in quasi-operating conditions by utilizing a personal computer (PC). The system utilizes a PC tester comprising a measurement PC unit that carries a memory module to be used as reference; a signal distribution unit for distributing the signal taken out form the measurement PC unit; a plurality of performance boards (PFBs) mounted with respective objected products to be observed simultaneously by using the signals distributed by the signal distribution unit; a display panel for displaying the current status of the test that is being conducted; a power source for producing the operating voltage of the system; and a control PC for controlling the selection of test parameters and various analytical operations.

Abstract: A semiconductor memory device, having a test mode and a normal mode, includes a frequency multiplier and a test command sequence generator. The frequency multiplier receives a test clock signal in the test mode and generates multiple internal test clock signals, each of which has a frequency equal to a frequency of an operation clock signal in the normal mode. The test clock signal has a frequency lower than the frequency of the operation clock signal. The test command sequence generator generates at least one command signal in response to the internal test clock signals in the test mode. The at least one command signal corresponds to at least one operation timing parameter of the semiconductor memory device that is to be measured. The frequency multiplier may include a Phase Locked Loop (PLL) or a Delay Locked Loop (DLL).

Abstract: An internal signal monitoring device in a semiconductor memory device includes: an internal signal input unit to receive an internal signal to be monitored and having an output to provide a monitor source signal in response to a test mode signal; and an internal signal output unit having an input coupled to the output of the internal signal input unit, the internal signal output unit to transmit the monitor source signal to a predetermined pad of the semiconductor memory device in response to the test mode signal.

Abstract: A method, system, and computer-usable medium for implementing a programmable DMA master with date checking utilizing a drone system controller. According to a preferred embodiment of the present invention, a drone processor generates a collection of random data and stores a first and second copy of the collection of random data in a first and second memory location in a drone memory. The drone processor writes a third copy of the collection of random data in a processor memory. When the drone processor retrieves the third copy from the processor memory, the drone processor writes the third copy in the second memory location in the drone memory. When the drone processor compares the first copy with the third copy, the results of the compare is written in a status location within the drone processor.

Abstract: Example embodiments of the present invention include a memory device testable without using data and a dataless test method. The memory device includes a plurality of registers to store test patterns, the registers being coupled to input/output DQ pads. The test patterns are stored in the registers when a mode register of the memory device is set. The memory device transfers the test patterns to a DQ pad responsive to a write test signal, and transfers the test patterns from the DQ pad to a data input buffer responsive to a read test signal. The memory device writes the test patterns transferred to the data input buffer to memory cells. The memory device reads data stored in the memory cells responsive to the write test signal and transfers the memory cell data from the DQ pad to a comparator responsive to the read test signal. The memory device compares the test patterns to the memory cell data transferred to the comparator and generates an indicator signal to indicate the comparison result.

Abstract: In a method for testing an embedded phase-locked loop (PLL) circuit, a first clock signal is provided to an embedded phase-locked loop (PLL) circuit to be tested. A PLL clock signal of a first frequency is generated by the embedded PLL in response to the first clock signal. The PLL clock signal of the first frequency is sampled with a second clock signal of a second frequency to generate a first sampled signal, wherein the second frequency is different from the first frequency but has a first correlation with the first frequency so that the first sampled signal toggles at a predetermined frequency when the embedded PLL circuit is in a normal operation condition. The embedded PLL circuit is determined to be in an abnormal operation condition if the first sampled signal does not toggle at said predetermined frequency.

Abstract: The present invention provides for a method for memory array verification. Initialization commands are received and memory array initialization settings are generated based on received initialization commands. The memory array initialization settings are stored in a memory array. A deterministic read output function for the memory array is identified and a logic built-in self test scan on the memory array is performed based on the identified deterministic read output function.

Abstract: Upon conduct of a test on a semiconductor memory in a merged LSI or the like, data signals from a small data bus width are simultaneously written to a plurality of memory cells of a memory core. Then, a coincidence detection circuit makes a comparison between data read from the plurality of memory cells in expectation of a coincidence thereof. When the coincidence detection circuit detects the coincidence of the data, a data compression circuit compresses the compared data, and then outputs the compressed data. On the other hand, when the coincidence detection circuit detects an anticoincidence of the data, the data compression circuit converts the different data into fixed data, and then outputs the converted data.

Abstract: In the initial setting of a memory card 1, the flash check data FD stored in a flash memory 2 is read out, this data FD is compared with the operation check data FD11 stored previously in the ROM, the write check data FD12 stored in the ROM 4a is written, if a fault is not detected, to the flash memory 2, and this data is read again and is compared with the write check data FD12 of the ROM 4a. When any fault is not detected in comparison of these data, the CPU determines that the flash memory 2 is normal. Moreover, if a fault is detected in the comparison of data, the CPU sets the reset process fault data to a register 5a to set a controller 3 to the sleep mode. When the command CMD is received during this period, data comparison is executed again.

Abstract: A system for, and method of, allowing conventional memory test circuitry to test parallel memory arrays and an integrated circuit incorporating the system or the method. In one embodiment, the system includes: (1) bit pattern distribution circuitry that causes a probe bit pattern generated by the memory test circuitry to be written to each of the memory arrays, (2) a pseudo-memory, coupled to the bit pattern distribution circuitry, that receives a portion of the probe bit pattern and (3) combinatorial logic, coupled to the pseudo-memory, that employs the portion and data-out bit patterns read from the memory arrays to generate a response bit pattern that matches the probe bit pattern only if all of the data-out bit patterns match the probe bit pattern.

Abstract: An integrated memory having a plurality of memory banks includes a test circuit for functional testing of the memory. A plurality of secondary sense amplifiers are assigned to a different one of the memory banks. The test circuit includes a data generator for generating read comparison data. A plurality of comparison circuits are assigned to a different one of the memory banks to compare test data read from the assigned memory bank with the read comparison data. A first input of the respective comparison circuit can be connected to the secondary sense amplifier without interposition of the read/write data lines. A second input can be connected to the read/write data lines to receive the read comparison data supplied by the data generator. An output signal of the respective comparison circuit depends on the comparison result of a data comparison of the first and second inputs.

Abstract: A method and apparatus according to the present invention enable wafer chips to be configured with a single power on and off sequence and further enable a chip parameter to be adjusted during a wafer test without utilizing that sequence. In particular, each wafer chip under test is assigned a unique programmable identification. Once each chip has been assigned a corresponding identification, the chips may each be individually accessible by that identification to provide parameter values to chip registers to configure that chip. The configured chips may be subsequently tested in parallel to evaluate the parameter settings. In addition, the present invention enables chips to share data I/O pins or lines, thereby reducing the quantity of testing machine pins utilized for each chip and enabling a greater quantity of chips to be tested in a parallel fashion.

Abstract: A method for testing semiconductor memory modules in which data are stored in banks with an addressable matrix structure containing rows and columns. Defect addresses of the defect locations in the banks are transmitted in compressed form to an external test device. The rows and/or the columns are subdivided into regions. The defects occurring in the respective region are counted row by row and/or column by column. The number of defects in each region is compared row by row and/or column by column with a threshold value, and the comparison results are transmitted as additional information row by row and/or column by column together with the defect addresses to a test device.

Abstract: The invention relates to a method and device for operating and/or testing memory units, which make it possible to conduct a time-saving test of semiconductor memories during running operation. The inventive method for testing memory units having storage locations provides that, for the storage locations, a first item of test information is formed according to a variable parameter assigned to the respective storage location and according to the contents of the respective storage location.

Abstract: Memory devices having a normal mode of operation and a test mode of operation are useful in quality programs. The test mode of operation includes a data compression test mode. In the data compression test mode, reading one word of an output page provides an indication of the data values of the remaining words of the output page. The time necessary to read and verify a repeating test pattern can be reduced as only one word of each output page need be read to determine the ability of the memory device to accurately write and store data values. The memory devices include data compression circuits to compare data values for each bit location of each word of the output page. Output is selectively disabled if a bit location for one word of the output page has a data value differing from any remaining word of the output page.

Abstract: The testing of a RAM memory circuit containing a multiplicity of memory cells can in each case be selected in groups of n?1 memory cells by using an applied address information item in order to write in or read out groups of in each case n data. According to the invention, in a test write cycle, a plurality i=j*m of the memory cell groups are selected, where j and m are in each case integers ?2, and the same datum is written into all the memory cells of in each case m selected memory cell groups. In a subsequent read cycle, the i memory cell groups selected in the write cycle are selected and read in a sequence such that the read-out data groups from in each case m memory cell groups at which the same datum was written in are provided simultaneously or in direct succession as a read data block comprising m*n data.

Abstract: A test arrangement with a test memory chip and a control device is provided. Error correction data are stored in the test memory chip with the aid of the control device. In the case of an error event, it is ascertained whether the error occurred on the error correction chip. If so, the memory controller compares the data stored in the error correction chip with the data of the auxiliary memory. The address of the error correction chip can be deduced from the address of the auxiliary memory, thereby enabling unambiguous addressing of a defective memory cell of the error correction chip.

Abstract: A self-test controller 10 is responsive to scanned in self-test instructions to carry out test operations including generating a sequence of memory addresses that is specified by the self-test instruction. Combining multiple such self-test instructions allows a custom test methodology to be built up by a user using a generic self-test controller 10.

Abstract: A memory circuit comprises a memory and a first test circuit coupled to the memory. The first test circuit is configured to compare data read from memory cells with expected data for the memory cells to provide a first set of pass/fail signals for the memory cells, compress the first set of pass/fail signals for the memory cells into a second pass/fail signal, latch the second pass/fail signal in response to a data valid signal, maintain the latch of the second pass/fail signal if the second pass/fail signal indicates a failed test, combine the second pass/fail signal and a third pass/fail signal of a second test circuit to provide a fourth pass/fail signal, and pass the fourth pass/fail signal to a third test circuit.

Abstract: A driver IC including: a plurality of output pads; and a plurality of signal switch circuits, each of the signal circuits being provided on one of signal paths respectively connected to the output pads, wherein each of the signal switch circuits switches between a first state (or a use state) in which a signal from an upstream side of the signal path is allowed to pass through the signal switch circuit and a second state (or an inspection state) in which a level pattern of signals from the output pads is fixed to an inspection level pattern, according to a control signal.

Abstract: A multi-bit write pointer that is associated with a first clock can be converted to a single-bit write pointer. A multi-bit read pointer that is associated with a second clock can be converted to a single-bit read pointer. The first clock and the second clock are not synchronized. One or more guard bits can be associated with the single-bit write pointer and/or the single-bit read pointer. The single-bit write pointer and the single-bit read pointer can be compared. According to an embodiment, an error can be detected in response to comparing the single-bit write pointer and the single-bit read pointer.

Abstract: Memory devices having a normal mode of operation and a test mode of operation are useful in quality programs. The test mode of operation includes a data compression test mode. In the data compression test mode, reading one word of an output page provides an indication of the data values of the remaining words of the output page. The time necessary to read and verify a repeating test pattern can be reduced as only one word of each output page need be read to determine the ability of the memory device to accurately write and store data values. The memory devices include data compression circuits to compare data values for each bit location of each word of the output page. Output is selectively disabled if a bit location for one word of the output page has a data value differing from any remaining word of the output page.

Abstract: The configuration of a faulty line segment in a switch matrix of a programmable logic device is identified using read-back capture. Each original programmable interconnection point (“PIP”) in the line segment is tested by generating routes from a first logic port through the original line segment and PIP, through all PIPs, adjacent to the original PIP to the opposite logic port. Routes through all PIPs adjacent to the PIPs in the line segment from the first logic port to the second logic port, and from the second logic port to the first logic port, are tested to isolate the fault in the line segment.

Abstract: Each memory chip of a memory module tests a total of N data bits from X memory blocks for efficient testing and outputs N/X test data bits from one of the memory blocks. A memory module includes a plurality of memory chips and a plurality of comparison units. Each comparison unit is disposed within a respective memory chip for testing a plurality of test data bits from a plurality of memory blocks. In addition, each comparison unit outputs test data bits from one of the memory blocks within the respective memory chip.

Abstract: A method and apparatus for detecting errors in a memory includes generating a first check word based on incoming data and generating a second check word based on stored data. The method includes comparing the first check word to the second check word, generating a comparison result, and indicating a failure based on the comparison result.

Abstract: A static random access memory (SRAM) unit is provided having a read control module, a write control module, and a bypass. The read control module is configured to communicate a read signal defined to read from a first address in the SRAM unit. The write control module is configured to communicate a write signal defined to write to a second address in the SRAM unit. The bypass is disposed to connect the write control module to the read control module. The bypass is further configured to prevent a simultaneous communication of the read signal and the write signal when the first address and the second address are equivalent.

Abstract: A DDR DRAM having a test mode and an operational mode and a method for testing the DDR DRAM. The method includes in the order recited: (a) placing the DDR DRAM in test mode; (b) issuing a band activate command to select and bring up a wordline selected for write of the DDR DRAM; (c) writing with auto-precharge, a test pattern to cells of the DDR DRAM; (d) repeating steps (b) and (c) until all wordlines for write have been selected; (e) issuing a bank activate command to select and bring up a wordline selected for read of the DDR DRAM; (f) reading with auto-precharge, the stored test pattern from cells of the DDR DRAM; and (g) repeating steps (c) and (f) until all wordlines for read have been selected.

Abstract: A semiconductor device having a plurality of circuits with the same configuration, wherein since expected values in the number corresponding to the number of circuits are not required, operation tests are effectively performed in a short time. The semiconductor device has first, second and third digital filters with the same configuration. To test these digital filters, comparison circuits comparing an output value and an expected value are individually provided per one digital filter. The digital filters and the comparison circuits are daisy-chained such that the output values of the first and second digital filters are input as the expected values of the comparison circuits corresponding to the second and third digital filters, respectively. When the same test signal is input to each digital filter from a built-in self test (BIST) controller, abnormal circuits can be detected based on comparison results of the comparison circuits.

Abstract: A testing device for a semiconductor storage device suppresses the increase in the circuit size, provides for facilitated accommodation to a test with frequent changes in the test pattern, and improves testability of the semiconductor storage device. A plurality of holding circuits are provided holding write data for memory cells of a memory cell array. (Original) The write data from the holding circuits are written in the memory cells of the selected address. A plurality of comparators are supplied with data read out from the memory cells and with data held by the holding circuits as expectation data to compare the readout data and the expectation data. The non-inverted or inverted value of the write data held by the holding circuits is output as the write data to the memory cells and as expectation data to the comparators depending on the value of the inversion control signal.

Abstract: A memory test circuit comprises a memory which outputs stored data through n-bit data output pins, and a built-in self test (BIST) unit. The BIST unit writes test data in the memory, and by comparing the test data output from the memory with expected data, determines a failure cell address in the memory. The BIST unit generates k preliminary failure signals having failure information indicating whether the test data correspond with the expected data, and outputs the k preliminary failure signals for m cycles of a clock signal, by outputting k/m preliminary failure signals each cycle as first through k/m failure signals. In the memory test circuit and test system, the BIST unit testing a memory and generating a failure signal is disposed in a memory apparatus and a failure analysis circuit analyzing a failure signal output by the BIST unit is disposed in the test apparatus.

Abstract: An integrated memory and method for testing an integrated memory is provided herein. In order to test an integrated memory having a main data memory with a plurality of data memory units, a data memory unit is addressed and input test data for testing the addressed data memory unit are applied to the main data memory. The output test data are read out from the main data memory and compared with expected desired output test data in a self-test unit. Deviations detected during the comparison are buffer-stored in a redundancy analysis memory. These information items buffer-stored in the redundancy analysis memory are read out and transferred to a computing unit. In the computing unit, the defect positions in the output test data are identified, and a repair strategy is determined by means of redundant rows and/or redundant columns and/or redundant words provided. The redundant words required for the repair strategy are written to the redundancy analysis memory and activated.

Abstract: A content addressable memory (CAM) device having concurrent compare and error checking capability. The content addressable memory (CAM) device includes circuitry to compare a comparand with a plurality of data words stored within the CAM device in a compare operation, and circuitry to determine, concurrently with the compare operation, whether one of the data words has an error.

Abstract: An error detection and correction circuit is connected to at least one memory bank of a CAM device. During background processing (i.e., when the CAM is not performing reading, writing or searching functions) the error detection and correction circuit tests all of the CAM locations that it is connected to in sequence. If an error is detected, the error detection and correction circuit rewrites the CAM location with the correct data. Multiple error correction and detection circuits can be used in the CAM device to test multiple CAM locations simultaneously.

Abstract: Apparatus and Method for Testing Circuit Units To Be Tested. According to one aspect, a test apparatus for testing circuit units to be tested, includes a nominal data production unit for production of a nominal data stream, a comparison device for comparison of an actual data stream which is emitted from the circuit unit to be tested as a function of the nominal data stream that is supplied with the nominal data stream; and a compression device for compression of an intermediate result signal which is emitted from the comparison device as a function of the comparison into a test result signal, with the intermediate result signal (108) which is emitted from the comparison device being temporarily stored in a buffer storage device with the intermediate result signal which is temporarily stored in a buffer storage device being read by means of a read unit.

Abstract: A cache may be programmed to disable one or more entries from allocation for storing memory data (e.g. in response to a memory transaction which misses the cache). Furthermore, the cache may be programmed to select which entries of the cache are disabled from allocation. Since the disabled entries are not allocated to store memory data, the data stored in the entries at the time the cache is programmed to disable the entries may remain in the cache. In one specific implementation, the cache also provides for direct access to entries in response to direct access transactions.

Abstract: Methods (400, 500, and 600) are disclosed for testing a memory device by tailoring an algorithm (460) used in the testing based on the preferred or intrinsic data state 425 that is obtained upon power-up of an advanced technology SRAM memory device (100). The methods (400, 500, and 600) take advantage of the observation that such SRAM devices repeatedly power-up in a preferred state 310. Accordingly, one method 500 comprises powering-up 510 the memory device and reading 520 a preferred power-up data state of each cell of the memory device without memory initialization or writes. The method 500 then captures and stores 530 a data state associated with the preferred power-up data state of each cell 100 and utilizes the stored power-up data state 310 or an inverse of the power-up data state 320 to tailor 540 a test pattern used by the test algorithm 460.

Abstract: A testing apparatus for performing a setup testing or a hold testing on a device under test (“DUT”) storing a given data signal according to a given clock signal is provided, wherein the testing apparatus includes a timing generating unit for generating sequentially a plurality of timing signals having different timings during the setup testing or the hold testing on the basis of a fist offset value given before starting the setup testing or the hold testing; a pattern generating unit for generating the clock signal and the data signal; a pattern formatting unit for shifting the phase of the data signal with respect to the clock signal sequentially according to the timing signals sequentially generated and providing the DUT with the clock signal and the phase-shifted data signal sequentially; and a determining module for acquiring a setup time or a hold time of the DUT on the basis of storage data which are the data signals stored by the DUT.

Abstract: A built-in self test circuit includes a capture register storing data transmitted from a memory device, an operation controller controlling operation of the memory device and the capture register, a hold controller executing a hold operation to stop a read operation and a write operation of the memory device by transmitting a hold signal to the operation controller, and a test control circuit controlling the operation controller to transmit a capture signal so that the capture register stores the data to the capture register.

Abstract: When ENG frames created in an ENG transceiver unit and ECT frames subjected to gateway processing in an ECT gateway processor are transmitted around the same time, a transmission mediating unit alternately transmits each of the ENG frames and the ECT frames. Therefore, as compared with a case where one type of frames are preferentially transmitted, transmission of both types of frames can be started at the earliest timing.