Abstract: A memory chip includes: a memory region; a chip determining unit configured to perform a chip determination, in writing operation, to determine whether or not the memory region is a writing target on the basis of an inputted address of writing destination, and to output a determination result of the chip determination; an address-cycle identifying unit configured to detect a final cycle of the address of writing destination, and to output a detection result at a timing before the output of the determination result; and a buffer controller configured to switch an input buffer from one state to another on the basis of the determination result, wherein the buffer controller keeps the input buffer in an active state irrespective of the determination result of the chip determination while the address-cycle identifying unit is outputting the detection result.

Abstract: A memory chip includes: a memory region; a chip determining unit configured to perform a chip determination, in writing operation, to determine whether or not the memory region is a writing target on the basis of an inputted address of writing destination, and to output a determination result of the chip determination; an address-cycle identifying unit configured to detect a final cycle of the address of writing destination, and to output a detection result at a timing before the output of the determination result; and a buffer controller configured to switch an input buffer from one state to another on the basis of the determination result, wherein the buffer controller keeps the input buffer in an active state irrespective of the determination result of the chip determination while the address-cycle identifying unit is outputting the detection result.

Abstract: A memory has a first bit line pair, a second bit line pair, a third bit line pair, a first data line pair, a second data line pair, a first transistor pair connecting the first bit line pair to the first data line pair, a second transistor pair connecting the second bit line pair to the second data line pair, a third transistor pair connecting the third bit line pair to the first data line pair, a fourth transistor pair connecting the third bit line pair to the second data line pair, a first selection line connected to the first transistor pair for switching ON/OFF of the first transistor pair, a second selection line connected to the second transistor pair for switching ON/OFF of the second transistor pair, a third selection line connected to the third transistor pair for switching ON/OFF of the third transistor pair, and a fourth selection line connected to the fourth transistor pair for switching ON/OFF of the fourth transistor pair.

Abstract: An improvement of a semiconductor memory device capable of designating a block write mode in which writing is effected simultaneously to a plurality of memory cells unitized by predetermined numbers and connected respectively to a plurality of column lines. Data lines correspond to a predetermined number of memory cells. The data lines and the column lines are selectively connected to each other by switches. During a block write mode, a predetermined number of column lines are simultaneously connected to the data lines corresponding thereto. During the other mode, a control unit controls the switches to connect some of the predetermined number of column liens to the data lines corresponding thereto. During the mode other than the block write mode, only a part of the predetermined number column lines are connected to the data lines, thereby reducing electric power consumption.

Abstract: A multiport semiconductor memory device of this invention is constructed as having: a RAM having a first RAM unit and a second RAM unit; a SAM having a first SAM unit and a second SAM unit; and transfer circuit capable of selectively taking one of a split transfer state and a cross transfer state, in the split transfer state the first RAM unit and the first SAM unit being connected together and the second RAM unit and the second SAM unit being connected together, and in the cross transfer state the first RAM unit and the second SAM unit being connected together and the second RAM unit and the first SAM unit being connected together.

Abstract: A semiconductor memory device comprises a memory cell array, a redundant memory cell array, bit line pairs, spare bit line pairs, a column address information storage circuit having stored therein information of a column address of a faulty cell and a column address of a spare cell, column decoders, a first column selecting gate for connecting one of the bit line pairs and first data output line pairs, a second column selecting gate for connecting one of the bit line pairs and a second data output line pair, a spare column decoder for selecting a third or a fourth column selecting line, a third column selecting gate for connecting the spare bit line pairs and the first data output line pairs, a fourth column selecting gate for connecting the spare bit line pairs and the second data output line pair, a first buffer for selecting two data and amplifying and outputting, a second buffer for amplifying and outputting data from the second data output line pair, and a register for storing therein data from the first

Abstract: A semiconductor memory device is disclosed which comprises, as shown in FIG. 1, a pair of column lines, memory cells connected to the corresponding column lines, a sense amplifier connected to the column lines, row lines for selecting the memory cells in accordance with a row address signal, and first and second transistors having their current paths connected between the column lines and a fixed potential supply terminal supplied with a positive power source potential or a ground potential, wherein the gates of the first and second transistors are connected to the first and second row lines for a data rewrite operation which can be selected independently of the row line.

Abstract: This invention provides a high potential hold circuit comprising: a high potential node; a high potential hold enhancement mode MOS transistor for holding a potential of the high potential node by setting the high potential hold transistor in an non-conducting state after the node is charged, having one end connected to a first input signal and the other end connected to the high potential node; a discharge enhancement mode MOS transistor for discharging the potential of the high potential node, having one end connected to the ground potential, the other end connected to the high potential node and a gate connected to a second input signal; a field relaxation enhancement mode MOS transistor located between the high potential node and the high potential hold transistor; and charge-discharge means for charging and discharging a potential of a gate of the field relaxation transistor.

Abstract: A flip-flop circuit has a power terminal set at 5 V, first and second output terminals, a latch section for charging one of the first and second terminals to 5 V and discharging the other one of the first and second terminals to 0 V in accordance with an input signal, a first MOS transistor having a current path connected between the power and first output terminals, a second MOS transistor for charging the gate of the first MOS transistor while the potential of the second output terminal is changed from 5 V to 0 V, and a capacitor for bootstrapping the gate potential of the first MOS transistor to turn on the first MOS transistor.