Fujitsu Corporation

Fujitsu Microelectronics Limited

Masaki Okuda

Hiroyuki Kobayashi

Toshiya Uchida

Yoshimasa Yagishita

Shusaku Yamaguchi

Yoshihide Bando

Atsushi Fujii

Shinya Fujioka

Kaoru Mori

Toshikazu Nakamura

Kota Hara

Waichiro Fujieda

Kazuyuki Kanazashi

Jun Ohno

Kouitirou Takahasi

Masahiro Yada

An address switch circuit receives a row address signal supplied to a first address terminal group and a column address signal supplied to a second address terminal group. Further, the address switch circuit receives the row address signal supplied to the second address terminal group and thereafter receives the column address signal supplied to the second address terminal group and supplies the received row address signal and the received column address signal to the row decoder and the column decoder during a second operation mode. The number of semiconductor memories that are tested at once can be increased by executing an operation test of the semiconductor memories in the second operation mode. In addition, it becomes possible to test a semiconductor memory using test assets for other semiconductor memories. Consequently, the test efficiency can be improved, and the test cost can be reduced.

Semiconductor memory, test method of semiconductor memory and system

To terminate startup of an application on an ASP side irrespective of checking on a user side whether or not the application is in the middle of processing. A monitoring device includes means monitoring an operating status of an information processing device for providing a service by starting up an information processing program to a user terminal specified by user identifying information, means judging whether or not the operating status of the information processing device meets a predetermined condition, means terminating the startup of the information processing program if the operating status meets the predetermined condition, and means notifying the user terminal of the termination of the startup of the information processing program.

Forced termination condition monitoring device, forced termination condition monitoring method and storage medium embodying forced termination condition monitoring program

A semiconductor memory has a memory cell array having dynamic memory cells. An access control circuit accesses the memory cells in response to an access command which is supplied externally. A refresh control circuit generates, during a test mode, a test refresh request signal in synchronization with the access command so as to execute a refresh operation of the memory cells when a refresh mask signal is at an invalid level. Also, the refresh control circuit prohibits generation of the test refresh request signal when the refresh mask signal is at a valid level. The test refresh request signal is generated or prohibited from being generated according to the level of the refresh mask signal. Thus, only a refresh operation needed for a test can be executed, and hence test efficiency can be improved.

Semiconductor memory and operating method of same

A semiconductor integrated circuit includes a semiconductor substrate, one or more wells formed in the semiconductor substrate, one or more diffusion layers formed in the one or more wells, a plurality of interconnects formed in an interconnect layer, the one or more diffusion layers and the plurality of interconnects being connected in series to provide a coupling between a first potential and a second potential, and a comparison circuit coupled to one of the interconnects set at a third potential between the first potential and the second potential, and configured to compare the third potential with a reference potential, wherein a first interconnect of the plurality of interconnects that is set to the first potential is connected to at least a first well of the one or more wells and connected to a first diffusion layer of the one or more diffusion layers that is formed in the first well.

Semiconductor integrated circuit for voltage detection

In order to prevent a signal of a signal wiring from receiving a bad influence due to a power supply capacitor, provided is a semiconductor including a high reference potential terminal and a low reference potential terminal composing power supply voltage terminals; a first MOS capacitor in which a gate of a p-channel MOS field effect transistor is connected to the low reference potential terminal, and a source and a drain are connected to the high reference potential terminal; and a first signal wiring connected to the gate via a parasitic capacitor and a signal in the low reference potential is supplied at the time of starting the power supply.

Semiconductor device

Semiconductor device having a power supply capacitor

A logical circuit receives first and second input signals in which a period of a first logic level partially overlaps, and outputs first and second output signals in which a period of the first logic level does not overlap. The logical circuit comprises a first unit which changes a phase of the first output signal from a second logic level to the first logic level when a change of the first input signal from the second logic level to the first logic level is detected. A second unit changes a phase of the second output signal from the first logic level to the second logic level when the second input signal is detected as being at the first logic level at a time of detection of the change of the first input signal.

Input/output logical circuit

Logical circuit

A semiconductor memory device is capable of simultaneously reading data and refreshing data and checking whether a data restoring function is operating normally. A data inputting circuit receives data inputted from an external circuit. A parity generating circuit generates parity data from the data input from the data inputting circuit. A memory stores the data input from the data inputting circuit and the parity data generated by the parity generating circuit. A refreshing circuit refreshes the memory. A reading circuit reads the data from the memory. A restoring circuit restores data to be refreshed by the refreshing circuit from other data read normally and corresponding parity data, while the reading circuit is reading data. A data outputting circuit outputs the data read by the reading circuit and the data restored by the restoring circuit. A parity outputting circuit directly reads and outputs the parity data stored in the memory.

Semiconductor memory device capable of simultaneously reading data and refreshing data

A plurality of first memory blocks and a second memory block for reproducing data of the first memory blocks are formed. When a read command and a refresh command conflict with each other, a read control circuit accesses the first memory block according to the refresh command and reproduces read data by using the second memory block. When a write command and the refresh command conflict with each other, a write control circuit operates the memory block according to an order of command reception. Therefore, it is possible to perform refresh operation without being recognized by users. Namely, a user-friendly semiconductor memory can be provided.

Semiconductor memory

A plurality of memory blocks is allocated the same address spaces to write the same data therein, and is operable independently of one another. One of the memory blocks is selected as a refresh block that performs a refresh operation, in response to a refresh command, while another one of the memory blocks is selected as a read block that performs a read operation, in response to a read command. Then, the plurality of memory blocks performs read operations at different timings so that the read operations overlap one another. Therefore, the semiconductor memory can receive read commands at intervals each of which is shorter than the execution time of a single read operation. As a result, externally supplied read commands can be responded to at high speed, and the data transmission rate during read operation can be improved.

A phase adjustment circuit delays an external clock signal to generate an adjusted clock signal. A phase comparator compares phases of the external clock signal and the adjusted clock signal, and outputs a phase adjustment signal for adjusting a delay time of the phase adjustment circuit. A data output circuit outputs read data to a data terminal in synchronization with the adjusted clock signal. A data input circuit receives write data supplied to the data terminal, in synchronization with the adjusted clock signal. When performing input of the write data and output of the read data successively, switching control between the input operation of the write data and the output operation of the read data only has to be completed within one clock cycle. The clock cycle can thus be reduced to the time required for the switching control. Consequently, maximum frequency of the external clock signal can be increased.

Semiconductor memory device

A semiconductor memory device includes a plurality of memory blocks, each of which is refreshed independently of one another, m (m>1) data pins, each of which continuously receives or outputs n (n>1) data pieces, a conversion circuit which converts data of each of the data pins between parallel data and serial data, m&times;n data bus lines on which the n data pieces are expanded in parallel with respect to each of the m data pins, m address selection lines which are connected to m respective blocks of the memory blocks corresponding to the m respective data pins, and are simultaneously activated, the activation of any one of the address selection lines connecting the data bus lines to a corresponding one of the m respective blocks and resulting in the n data pieces being input/output to/from the corresponding one of the m respective blocks.

Semiconductor memory device having error correction function for data reading during refresh operation

One aspect of the present invention is that, when the memory is in the non-power-down state, the supply of clock signals to the data output circuit is limited to the read status after the reception of a read command, and no clock signal supply is performed when either the active status or the write status is in effect. In the best aspect, furthermore, in the read status after the reception of a read command, the supply of clock signals to the data output circuit starts after a number of clock signals corresponding to a set CAS latency following the read command, and stops after a number of clock signals corresponding to a set burst length, after the output of the read out data from the data output circuit starts. Accordingly, even in the non-power-down state, clock signals are only supplied during the time required for the read out data to be actually output from the data output circuit to the outside, whereby it is possible to reduce the number of clock signal supply actions that require large current drive.

Memory device

A semiconductor device includes a device-type switching circuit which determines selection signals A based on fuse-cut conditions in a first mode, and determines selection signals based on control signals supplied thereto in a second mode, and an internal circuit having an operation thereof selected by selection signals from device-type switching circuit.

Growing community of inventors

Kawasaki, Japan

Masaki Okuda