53 results about "Memory defects" patented technology

Methods and apparatus for maintaining and utilizing system memory defect tables that store information identifying defective memory locations in memory modules. For some embodiments, the defect tables may be utilized to identify and re-map defective memory locations to non-defective replacement (spare) memory locations as an alternative to replacing an entire memory module. For some embodiments, some portion of the overall capacity of the memory module may be allocated for such replacement.

The present invention provides a high-capacity and reliable semiconductor device which does not require additional circuits for use at power ON / OFF, additional steps nor high manufacturing cost, and which has a rectifier means for rectifying a defect easily. A semiconductor device comprises a first memory means including a memory cell and a redundant memory cell each including a memory element in the region where a bit line and a word line cross each other with an insulator interposed therebetween, a second memory means for storing an address of a defective memory in the first memory means, a rectifier means including a holding means and a replacement means, and an inspection means for writing data of the second memory means to the holding means. The replacement means replaces the defective memory cell with the redundant memory cell. In addition to the aforementioned four means, a display means for displaying images is provided as well.

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. Further, a first communication link is provided for connecting each of the test wrapper units directly to the test controller, and a second communication link is provided for connecting each test wrapper unit in an ordered sequence with the test controller. When controlling performance of the sequence of tests, the test controller provides first test data via the first communication link and second test data via the second communication link. It has been found that such an approach provides a particularly efficient and flexible technique for performing BIST functions within the integrated circuit.

A method is provided for managing defects in a semiconductor memory system having a plurality of addressable locations. In the method, a first plurality of the addressable locations is allocated as in-use locations, and a second plurality of the addressable locations is allocated as spare locations. A plurality of sets of the in-use locations, wherein each of the sets is associated with a memory defect, is determined. At least one of the sets includes a different number of in-use locations than another of the sets. Each of the sets of the in-use locations is associated with at least one corresponding set of the spare locations. Each of a plurality of data requests that is associated with one of the sets of the in-use locations is directed to the at least one corresponding set of the spare locations.

If a memory block in a flash memory device is found to have a defect, a memory block quality indication is generated in response to the type of memory defect. This indication is stored in the memory device. In one embodiment, the quality indication is stored in a predetermined location of the defective memory block. Using the quality indication, it can be determined if a system's error correction code scheme is capable of correcting data errors resulting from the defect.

There are provided a failure repair analyzing and processing method and a memory testing apparatus provided with a failure repair analyzing and processing apparatus using this method, that are capable of reducing a time duration required to perform the failure repair analysis and processing for a multi-bit memory having redundancy structure. A plurality of repair analysis units as well as a common failure analysis memory are provided, and these repair analysis units are concurrently operated in parallel with each other, thereby to carry out respective repair analyses and processings for failure memory cells of plural data bits read out from the failure analysis memory in the plural repair analysis units concurrently and in parallel with each other. As a result, a time duration required to execute the failure repair analysis and processing is shortened.

An integrated circuit and method for testing memory on that integrated circuit includes processing logic operable to perform data processing operations on data, and a number of memory units operable to store data for access by the processing logic. A memory test controller is also provided for executing test events in order to seek to detect any memory defects in the number of memory units. The controller includes a storage operable to store event defining information for each of a plurality of test events forming a sequence of test events to be executed, and an interface which, during a single programming operation, receives the event defining information for each of the plurality of test events and causes that event defining information to be stored in the storage. Event processing logic within the controller is then operable, following the single programming operation, to execute the sequence of test events.

The invention provides a detection method, system and device using the released memory and a storage medium. The method comprises the following steps of inputting a program to be detected; generatinga symbolic expression diagram for each function in the program, wherein a symbolic expression graph consists of nodes and edges that connect nodes, the node includes a value node and an operator node,and the edge includes a data dependency edge and a control dependency edge, wherein the data dependency edge is a directional edge connecting the node to a value node with which it has a direct datadependency relationship, and the control dependency edge is a directional edge connecting the variable to the condition when there is a condition defining the variable; detecting whether the constraint conditions of the path from the source node of the symbolic expression graph to the object node of the object in which the memory release operation is performed are met, If so, finding a memory defect after the use of the released memory. The invention can efficiently detect the defect after the use of the released memory by utilizing the judgment of the path and the path constraint conditions in the symbol expression diagram.

According to some embodiments, a memory device having multiple memory units includes one or more redundant memory units. Upon detection of an electrical characteristic indicating a failing memory unit, one of the redundant memory units is used to replace the failing memory unit. Detection of failing memory units may be via current, voltage and / or resistance monitoring. If the electrical characteristic monitored exceeds a predetermined threshold, a memory unit is considered failing. The failing memory unit is removed from further use. The redundant memory unit is programmed to be accessible at the memory address of the removed memory unit. Replacement occurs automatically (that is, without user intervention).

A system and method for defect analysis of multi-level memory cell devices and embedded multi-level memory in system-on-chip integrated circuits are disclosed wherein a defect data set is input into the system. When a defect data set is received, an automated test engineering system running a memory test program analyzes the defect data set to generate one or more fail bit locations and one or more fail states of the memory. The multi-level memory defect analysis system and method then classify failed bits or patterns comprising a vertical fail pattern, whereby after being classified, each memory cell failure vertical fail pattern has three data attributes comprising fail type, a number of fail bits / states, and a sequence of the fail states. The vertical fail pattern may comprise a single fail state or multi-state fail. The multi-state fail may be a continuous-states fail, discontinuous-states fail, or all-state fail. The multi-level memory defect analysis system and method may additionally enable classification of failed bits or patterns comprising a lateral fail pattern. The lateral fail pattern may be a gradual fail pattern, periodic fail pattern, or random fail pattern.

A life parameter generator generates life parameters related to the life of a nonvolatile memory device by using parameters related to allowable capacity for memory defect and occurrence capacity for memory defect. The life parameters are stored in a life parameter storing block of a nonvolatile memory. An access device reads and displays the stored life parameters. Thus, the user can precisely know the life of the nonvolatile memory device or the moment when a device having a built in nonvolatile memory such as a portable audio becomes unusable.

In an information processor including memory devices such as DRAMs and others, by reducing the power consumption of memory devices and efficiently repairing defect bits, a highly reliable information processor is realized. In an information processor including an external memory such as a DRAM, a second memory whose power consumption at the access time is smaller than that of the external memory is disposed, and cache data of the external memory and repair data are stored in this second memory. To an input address given from a central processing unit via a primary cache controller, a memory controller determines a hit or a miss with reference to a tag memory for cache and a tag memory for repair, and when one or both of tag memory for cache and a tag memory for repair are hit, it accesses the second memory.