Abstract: A semiconductor memory device that reduces the probability of the penalties of wirings arising. An address input circuit receives an address signal input. A drive circuit drives a memory array in compliance with the address signal. A signal line connects the address input circuit and the drive circuit. A redundant circuit is located near the drive circuit and substitutes other lines including a redundant line for a defective line in the memory array. A defective line information store circuit stores information showing the defective line. A supply circuit supplies information stored in the defective line information store circuit to the redundant circuit via the signal line. This structure enables to transmit an address signal and information regarding a defective line by a common signal line and to reduce the number of wirings and the probability of the penalties of wirings arising.

Abstract: A semiconductor memory device has a read data line, a write data line, a data holding circuit, and a data writing circuit. The data holding circuit holds data on the write data line, and the data writing circuit writes the data held on the write data line into a memory cell. Further, a semiconductor memory device has a read data line, a write data line, and an address information holding circuit. The address information holding circuit holds address information that is input in relation to write data, and when an access occurs to the address held in the address information holding circuit, data held on the write data line is written into a memory cell corresponding to the address.

Abstract: Data is stored into a plurality of first memory blocks, and regeneration data for regenerating this data is stored into a second memory block. In a read operation, either a first operation for reading the data directly from a first memory block selected or a second operation for regenerating the data from the data stored in unselected first memory blocks and the regeneration data stored in the second memory block is performed. This makes it possible to perform an additional read operation on a first memory block during the read operation of this first memory block. Therefore, requests for read operations from exterior can be received at intervals shorter than read cycles. That is, the semiconductor memory can be operated at higher speed, with an improvement in data read rate.

Abstract: Signals supplied to predetermined terminals are accepted as commands at a plurality of times, the number of operating modes is sequentially narrowed down based on the command each time and an internal circuit is controlled according to the narrowed operating modes. Since the information necessary for determining an operating mode is accepted at a plurality of times, the number of terminals necessary for inputting commands can be reduced. In particular, in case of inputting commands at a dedicated terminal, its input pads, input circuits, or the like are no longer be required so that the chip size can be reduced. The reduction is accomplished by reducing the number of terminals, which gives limits to the package size. The command controlling circuit with a plurality of accepting circuits is comprised. Each of the accepting circuits respectively accepts signals, supplied at a plurality of times, each time.

Abstract: A semiconductor device mounted on a board or the like and having a test circuit, having the function of carrying out a contact test at a low cost on the terminals of the semiconductor, is disclosed. The semiconductor device comprises a terminal test circuit for testing a state of a contact of an external terminal and a test mode control circuit unit. The test mode control circuit unit outputs a signal indicating a first operation mode upon application of a power supply voltage thereto, outputs a test mode signal to the terminal test circuit in response to a control signal input to a specific terminal such as a chip select terminal, and outputs a signal indicating a second operation mode in response to the number of times in which the level of the control signal input to the specific terminal changes. Preferably, the first operation mode is a terminal test mode, and the second operation mode is a normal operation mode.

Abstract: A semiconductor memory device includes isolation circuits disconnecting cell arrays from sense amplifiers, and isolation signal generating circuits generating isolation signals that control the isolation circuits. The isolation signal generating circuits are hierarchically divided into main isolation signal generating circuits and sub isolation signal generating circuits. The sub isolation signal generating circuits generate sub isolation signals having a first potential on a high-potential side. The main isolation signal generating circuits generate main isolation signals having a second potential on the high-potential side, the second potential being lower than the first potential.

Abstract: A semiconductor memory device has a burst write mode in which predetermined plural command signals are input through a plurality of command pads and a mask control operation in the burst write mode is performed in response to the command signals. Therefore, the mask control in burst write mode is increased in speed to give an improved data transfer rate.

Abstract: A semiconductor memory device includes isolation circuits disconnecting cell arrays from sense amplifiers, and isolation signal generating circuits generating isolation signals that control the isolation circuits. The isolation signal generating circuits are hierarchically divided into main isolation signal generating circuits and sub isolation signal generating circuits. The sub isolation signal generating circuits generate sub isolation signals having a first potential on a high-potential side. The main isolation signal generating circuits generate main isolation signals having a second potential on the high-potential side, the second potential being lower than the first potential.

Abstract: A semiconductor memory device having an internal circuit includes a command decoder which decodes input-command signals to supply decoded-command signals, an address-latch-signal-generation circuit, operating faster than the command decoder, which decodes the input-command signals to supply an address-latch signal, and a control circuit which controls the internal circuit based on the decoded-command signals. The semiconductor memory device further includes an address-input circuit which latches an address signal in response to the address-latch signal.

Abstract: A semiconductor memory device and information processing unit that improve speed at which data is written in a semiconductor memory device. A transfer section transfers data in a burst mode. A transferred number setting section sets the number of a plurality of bits of data transferred in the burst mode. A write command input section receives an input write command. A timing section measures time which has elapsed after the write command being input. A write start time setting section sets time which elapses before the writing of data being begun, according to the number of bits of data set by the transferred number setting section.

Abstract: A semiconductor memory device has a burst write mode in which predetermined plural command signals are input through a plurality of command pads and a mask control operation in the burst write mode is performed in response to the command signals. Therefore, the mask control in burst write mode is increased in speed to give an improved data transfer rate.

Abstract: 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×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.

Abstract: A semiconductor memory device includes isolation circuits disconnecting cell arrays from sense amplifiers, and isolation signal generating circuits generating isolation signals that control the isolation circuits. The isolation signal generating circuits are hierarchically divided into main isolation signal generating circuits and sub isolation signal generating circuits. The sub isolation signal generating circuits generate sub isolation signals having a first potential on a high-potential side. The main isolation signal generating circuits generate main isolation signals having a second potential on the high-potential side, the second potential being lower than the first potential.

Abstract: A semiconductor memory device which permits access even during refresh operation and also is low in power consumption. An address input circuit receives an input address, and a readout circuit reads out data from at least part of a subblock group arranged in a column or row direction and specified by the address input via the address input circuit. A refresh circuit refreshes at least part of a subblock group arranged in a row or column direction and intersecting with the subblock group from which data is read out by the readout circuit. A data restoration circuit restores data of a subblock where refresh operation and readout operation take place concurrently, with reference to data from the other subblocks and a parity block.

Abstract: The current generating unit in the transmitter generates output currents in accordance with a plurality of logic values. The reference current generating unit in the receiver generates a plurality of reference currents. The current comparing units in the receiver respectively compares reference currents with output current from the transmitter and restores the logic values. That is, the current is varied in correspondence with the logic values that are transmitted from the transmitter to the receiver, wherein the logic values are restored in the receiver according to a difference in the current value. Forming a plurality of current comparing units in the receiver makes it possible to easily compare the values of the output current from the transmitter and a plurality of reference currents. Therefore, the number of multi-valued bits can be easily increased so as to construct a high bit-rate multi-valued input/output interface.

Abstract: 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.

Abstract: 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×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, and a parity data comparison circuit which performs a parity check on m data pieces read from the m respective blocks corresponding to the m respective data pins a

Abstract: A semiconductor memory device capable of shortening the command supply interval during random access and thus improving the transfer rate of input/output data. In response to a write command, identical data is written into multiple memory banks having identical addresses assigned thereto. At this time, a bank selection circuit sequentially selects the memory banks to initiate write operations in a staggered manner. Since the write operation can be started before all memory banks become idle, the interval between the supply of read command and the supply of write command can be shortened. Consequently, the number of commands supplied per given time can be increased, and since data signal can be input/output more frequently than in conventional devices, the data transfer rate (data bus occupancy) improves. As a result, the performance of a system to which the semiconductor memory device is mounted can be enhanced.

Abstract: The current generating unit in the transmitter generates output currents in accordance with a plurality of logic values. The reference current generating unit in the receiver generates a plurality of reference currents. The current comparing units in the receiver respectively compares reference currents with output current from the transmitter and restores the logic values. That is, the current is varied in correspondence with the logic values that are transmitted from the transmitter to the receiver, wherein the logic values are restored in the receiver according to a difference in the current value. Forming a plurality of current comparing units in the receiver makes it possible to easily compare the values of the output current from the transmitter and a plurality of reference currents. Therefore, the number of multi-valued bits can be easily increased so as to construct a high bit-rate multi-valued input/output interface.

Abstract: The current generating unit in the transmitter generates output currents in accordance with a plurality of logic values. The reference current generating unit in the receiver generates a plurality of reference currents. The current comparing units in the receiver respectively compares reference currents with output current from the transmitter and restores the logic values. That is, the current is varied in correspondence with the logic values that are transmitted from the transmitter to the receiver, wherein the logic values are restored in the receiver according to a difference in the current value. Forming a plurality of current comparing units in the receiver makes it possible to easily compare the values of the output current from the transmitter and a plurality of reference currents. Therefore, the number of multi-valued bits can be easily increased so as to construct a high bit-rate multi-valued input/output interface.