Fujitsu Corporation

Rikizo Nakano

Osamu Ishibashi

Sadao Miyazaki

Noriyuki Matsui

Yoshinori Mesaki

A memory module includes a plurality of memory chips stacked on top of one another, each of the plurality of memory chips including a memory cell unit that is divided into a plurality of blocks, and an address scrambling circuit that processes an input address signal and that selects a block to be operated.

Memory module and semiconductor storage device

A semiconductor memory device is disclosed that includes an ODT circuit configured to be connected to a bus which transmits a data signal or a data strobe signal between a memory block and an input-output terminal; a first switch configured to be inserted into the bus between the memory block and the ODT circuit; a mode controller configured to switch off the first switch during a test of the memory block; and an oscillator configured to be connected to the ODT circuit, wherein a test signal is supplied to the ODT circuit from the oscillator during the test of the memory block.

Semiconductor memory device and information processing apparatus including the same

A memory error detecting apparatus for detecting an error of a subject memory, the memory error detecting apparatus includes a memory bus connected to the subject memory, a mirror memory connected to the memory bus so as to receive the same data as data to be written into and read from the subject memory, the received data being written into the mirror memory, an address acquiring portion configured to acquire an address related to the data written into the subject memory, a mirror memory controller configured to control data writing or reading to or from the mirror memory on the basis of the acquired address, a comparator configured to compare data read from the subject memory and data read from the mirror memory, and an error detector configured to detect a data error on the basis of a result of the comparison.

Memory error detecting apparatus and method

A memory control device is provided. The memory control device is configured to control access to a storage device including a plurality of storage areas. The memory control device includes a defect detecting unit configured to detect a defective area of a storage area into which data may not be stored. The memory control device also includes a storage processing unit configured to store defect information including address information of the defective area detected using the defect detecting unit into a memory area. A data writing unit is also included in the memory control device. The data writing unit is configured to write data, which has been written into the defective area, into a storage area other than the storage area comprising the defective area based on the defect information stored using the storage processing unit.

Memory controlling apparatus and method

A memory system includes a first memory that is used as a main memory of a target device, a second memory that has an access speed lower than that of the first memory, a securing section that secures a predetermined area of the first memory as a temporary storage area of the second memory, and a memory control section that receives an instruction to write data into the second memory, temporarily stores the data into the first memory and also transfers the stored data from the first memory to the second memory.

Memory system and information processing device

A test apparatus for testing a memory device including a memory cell. The test apparatus includes a storage and a controller. The storage stores a first value. The controller executes, at a given timing, determining a second value which is a threshold limit value to read data of the memory cell correctly on the basis of an output of the memory cell, calculating a difference between the first value and the second value, outputting a deterioration information on the basis of the difference between the first value and the second value, and updating the first value stored in the storage to the second value.

Test apparatus and test method for testing a memory device

A data processing apparatus includes a CPU including a register, a cache memory, a main memory configured to exchange data with the cache memory, a control part configured to control the exchanging of data between the main memory and the cache memory, and a power supply part configured to supply power to the register, the cache memory, and the main memory. The register, the cache memory, and the main memory are each configured to store data and maintain the stored data therein without being supplied with the power from the power supply part. The control part is configured to stop the CPU from accessing the register, the cache memory, and the main memory where an abnormality occurs in the power supply part.

Data processing apparatus

An electronic device test method incorporating a stress application step that is effective in screening out infant mortality failures of an electronic device. More specifically, a method for testing an electronic device constructed from a single or a plurality of semiconductor components, includes: turning a power supply on and off repeatedly while changing the ON/OFF cycle and/or voltage value of the power supply that is connected to the electronic device; and verifying whether or not the electronic device operates normally after the power supply has been turned on and off repeatedly.

Method and apparatus for testing electronic device

An IC element testing device includes a test pattern generating unit for generating test patterns, a power supply unit for generating a power supply voltage, a superposed voltage generating unit for generating a superposed voltage, and a superposing unit for superposing the superposed voltage on the power supply voltage and for outputting a superposed power supply voltage to an IC element to which the test patterns generated by the test pattern generating unit are applied.

IC element testing device

A method of testing bit lines of a memory unit includes the steps of alternately writing a set of first binary values and a set of inverted first binary values to blocks having even block values and to blocks having odd block values for all storage elements within each of a plurality of blocks of the memory unit; setting the memory unit to a stressed condition; alternately reading pieces of binary data from first-row storage elements of the blocks having even block values and from final-row storage elements of the blocks having odd block values by repeatedly inverting a row value of a memory address and incrementing a block value of the memory address for each block; setting the memory unit to a normal condition; and repeating the first setting step, the alternate reading step, and the second setting step for all the columns of the plurality of the blocks.

Growing community of inventors

Kawasaki, Japan

Rikizo Nakano