摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A memory device comprises: a plurality of banks each of which includes an array of memory cells; and at least a first and a second internal power generator, provided for each of the plurality of banks, for generating an internal power source voltage which differs from a voltage supplied by an external power source. If the internal common power source voltage in the memory device is lower than the first voltage when the power is on, the first and the second internal power generators in a plurality of banks are activated so as to rapidly raise the common internal power source voltage. When the common internal power source voltage in the memory device is higher than the first voltage and lower than the second voltage, the second internal power generators in the banks are activated to compensate for a drop in the internal power source voltage, which is caused by current leakage. When the internal power source voltage in a bank in the activated state is lower than the third voltage, the first and the second internal power generators in the corresponding bank are activated and satisfactorily drive the internal power source voltage in the bank so as to operate the memory device at a high speed.
摘要:
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.
摘要:
An image memory, image memory system, and memory controller that are capable of efficiently accessing a rectangular area of two-dimensionally arrayed data are provided. The memory device has: a memory cell array that has a plurality of memory unit areas, each of which is selected by addresses; a plurality of input/output terminals; and an input/output unit provided between the memory cell array and the plurality of input/output terminals. Each of the memory unit areas stores therein data of a plurality of bytes or bits corresponding to the plurality of input/output terminals respectively, and the memory cell array and the input/output unit access a plurality of bytes or bits stored in a first memory unit area corresponding to the input address and in a second memory unit area adjacent to the first memory unit on the basis of the input address and combination information of the bytes or bits in response to a first operation code, and then, from the plurality of bytes or bits within the accessed first and second memory unit areas, associate a combination of the plurality of bytes or bits based on the combination information, with the plurality of input/output terminals.
摘要:
An image memory, image memory system, and memory controller that are capable of efficiently accessing a rectangular area of two-dimensionally arrayed data are provided. The memory device has: a memory cell array that has a plurality of memory unit areas, each of which is selected by addresses; a plurality of input/output terminals; and an input/output unit provided between the memory cell array and the plurality of input/output terminals. Each of the memory unit areas stores therein data of a plurality of bytes or bits corresponding to the plurality of input/output terminals respectively, and the memory cell array and the input/output unit access a plurality of bytes or bits stored in a first memory unit area corresponding to the input address and in a second memory unit area adjacent to the first memory unit on the basis of the input address and combination information of the bytes or bits in response to a first operation code, and then, from the plurality of bytes or bits within the accessed first and second memory unit areas, associate a combination of the plurality of bytes or bits based on the combination information, with the plurality of input/output terminals.
摘要:
A semiconductor integrated circuit device has a boosted-voltage power-supply circuit generating a boosted voltage, an internal circuit being driven with the boosted voltage, and a control circuit controlling the internal circuit by receiving the boosted voltage. The boosted-voltage power-supply circuit has a first output terminal for the internal circuit, and a second output terminal for the control circuit. The boosted voltage output from the second terminal has a specified level regardless of variation in the boosted voltage being output from the first terminal.