摘要:
A nonvolatile semiconductor memory device having a first memory cell array including a plurality of electrical reprogramming and erasable nonvolatile semiconductor memory cells formed in a first area of a semiconductor substrate, a second memory cell array including a plurality of electrical reprogramming and erasable nonvolatile semiconductor memory cells formed in a second area different from said first area of said semiconductor substrate, said first and second memory cell arrays being arranged in a first direction, and a first pad section for inputting data to and outputting data from said first memory cell array and said second memory cell array, said first pad section having a plurality of pads arranged between said first memory cell array and said second memory cell array along a second direction perpendicular to said first direction.
摘要:
In an FCRAM having a late write function, when a first command signal indicates “write active”, whether a write operation or an auto-refresh operation is to be performed is determined on the basis of a second command signal. For example, when the second command signal indicates “write”, a write operation for a memory cell is performed by a late write scheme. When the second command signal indicates “auto-refresh”, an auto-refresh operation is performed. In the last write cycle of a write operation immediately preceding this auto-refresh operation, addresses for selecting a memory cell as an object of auto-refresh are predetermined. After data write to a memory cell is completed in the last write cycle, row precharge for auto-refresh is performed. After that, an auto-refresh operation (i.e., a data read operation and a data restore operation) is performed for the selected memory cell.
摘要:
A synchronous semiconductor memory device includes a plurality of memory banks which read data from memory cells and write data into the memory cells, a command decoder circuit which receives a command, detects whether the command is a read command or a write command, and, when detecting a read command or a write command, outputs a first control signal that enables a read operation or a write operation in the plurality of memory banks, bank select circuits which activate a second control signal to activate each of the memory banks, and bank timer circuits which deactivate the activated second control signal and perform control in such a manner that the timing with which the second control signal is deactivated in a test mode differs from that in a normal mode.
摘要:
In the package, a semiconductor chip is accommodated. This semiconductor chip has n pads (n is a natural number). The package has n pins connected to n pads.
摘要:
A clock synchronous circuit is stopped or started in accordance with the situation. More specifically, the clock synchronous circuit is stopped when no synchronous clock is necessary or in modes, such as a standby mode, bank active mode, refresh mode, and write mode, other than a read mode. In the read mode, the clock synchronous circuit is operated because a synchronous clock is necessary to output data. In the read mode, the number of clocks, i.e., CL, required from the time a read command is input to the time data is actually output, is 3 or more, when restarting and preamble of the clock synchronous circuit are taken into consideration.
摘要:
The data output circuit in a clock synchronous DRAM comprises a first data transfer circuit to which the data read from a memory is input and which transfers the input data to the output side in synchronization with an internal clock, an equalizing circuit to which the output of the first data transfer circuit is input during a read operation by a burst operation and to which high-impedance data is input after the read operation, a second data transfer circuit connected to the equalizing circuit, and an output buffer to which the output of the second data transfer circuit is input. The second data transfer circuit transfers all the data to the output buffer in synchronization with an output clock. This eliminates the dependence of the data access time and data hold time on data item and/or cycle and facilitates the timing control of the output control signal.
摘要:
A synchronous dynamic random access memory has spare columns which can be tested before shipping. In the memory, a mode set register outputs a multibank write signal in the test mode. A CBS latch circuit generates not only a signal for selecting the spare column decoders in banks and in the test mode but also signals for selecting the column decoders. Write driving circuits write the data onto the column lines selected by the column decoders and onto the spare column lines selected by the spare column decoders.
摘要:
A semiconductor memory device having a plurality of banks of memory cells is provided. The device has a data line provided in each of the banks for coupling to one of the memory cells in the corresponding bank. A common data line is shared by the banks, and is selectively coupled to one of the data lines through switches. Additionally, an amplifier is coupled to the common data line to amplify data read from a selected memory cell, and an I/O line is coupled to the amplifier to transmit the amplified data to an outer section. In the device, one of the banks of memory cells is selected by a bank select signal. Therefore, the amplifier is shared by the banks. Further the length of the I/O line can be shortened so that the load on the amplifier can be reduced. Accordingly, chip area is decreased and the speed of the memory device is improved.
摘要:
The present invention provides a semiconductor memory circuit capable of high-speed access to a predetermined column portion by a simplified high-speed addressing circuit. The memory circuit in a DRAM is such that a portion of a column addressing circuit normally comprising a counter constitutes a shift register in a column addressing circuit at a preceding stage of a column address buffer so that a plurality of address signal wrappings are realized for accessing the predetermined column portion.
摘要:
A semiconductor integrated circuit includes a rectangular semiconductor chip having a main surface, a plurality of pads formed in a peripheral portion of the main surface of the semiconductor chip, for connection to external connecting members, a plurality of circuit elements of an integrated circuit formed in an area of the main surface other than an area in which the plurality of pads are formed, and at least one characteristic evaluating circuit element connected to at least one of the plurality of circuit elements of the integrated circuit by sharing an impurity doped region which forms part of the at least one circuit element with the at least one circuit element of the integrated circuit in an area of the main surface other than the peripheral portion in which the plurality of pads are formed.