Abstract: A plurality of word drivers are provided corresponding to a plurality of word lines. A switch band is provided between the plurality of word drivers and a plurality of row decoders. Each row decoder is connected to four word drivers through the switch band. The state of connection between each of the row decoders and the word driver can be changed by the switch band. A spare row decoder, four word drivers and four spare word lines are provided. Any of the row decoders can be replaced with the spare row decoder. Consequently, four spare word driver and four spare word lines can be selected instead of the four word drivers and four word lines connected to the row decoder.

Abstract: In a block access memory, the memory cell array is divided into a plurality of blocks, one word line is selected based on the external address and the access to the memory cells connected thereto is carried out in one block and, simultaneously, one word line is selected based on the internally generated refresh address and the refresh of the memory cells connected to the word line is carried out in the other block.

Abstract: A semiconductor memory comprises a data bit memory cell array (3), a check bit memory cell array (4), and an address decoder (19) which includes a switching circuit (20) for selectively accessing data from either the memory cell array (3) or (4). Decoding signals d.sub.l to d.sub.m are used for reading out data latched by a column address strobe (CAS) signal. The decoding signals are applied to either the memory cell array (3) or (4) through a group of switching elements selectively rendered conductive by complementary signals .phi. and .phi.. The logical values of the signals .phi. and .phi. change responsive to a change in the CAS signal state.

Abstract: A circuit for generating a boosted signal for a word line, coupled to a word line driving signal line for transmitting a voltage signal to the word line, coupled to a first power supply, and coupled to a second power supply for providing a voltage higher than the voltage of the first power supply, can supply a compensating voltage for the word line from the second power supply through the word line driving signal line when a voltage of the word line is decreased.

Abstract: A word length variable circuit of a semiconductor memory comprises a shift register provided corresponding to rows or columns of a memory cell array. The input of the first stage of the shift register is connected to the output of the last stage and regions of the shift register is grouped to form a fixed recirculation path. The word length can be varied by modifying stored data in the shift register without changing its recirculation path.

Abstract: A dynamic semiconductor memory device comprising a substrate having one trench including two capacitors for memory cell capacitances of two bits, and two elements such as transistors for reading, writing, and storing information represented by charge, arranged symmetrically at the central portion of the trench so as to correspond to the memory cells for two bits, and a field oxide film formed at the center of the trench on the bottom and on the side walls for separating the capacitors and elements.

Abstract: A dynamic RAM comprises an array of memory cells, each of the memory cells comprising a single access transistor and a charge storage region. The charge storage region comprises a first capacitor memory including a P.sup.+ region serving as an opposite electrode formed in the inner surface of a trench formed in a P type silicon substrate, a first capacitor dielectric film formed on the P.sup.+ region and a common electrode layer serving as a memory terminal formed on the first capacitor dielectric film, and a second memory capacitor including the common electrode layer, a second capacitor dielectric film formed on the common electrode layer and a cell plate electrode formed on the second capacitor dielectric film. The memory terminal and a drain region of the access transistor are connected in a self-aligning manner by an electrode having a sidewall shape which is in contact with an end of the memory terminal.

Abstract: A semiconductor memory device comprises a plurality of memory cells arranged in a plurality of rows and columns, a plurality of row decoders for selecting one row of the plurality of rows, spare memory cells arranged in one row and a spare decoder for selecting the spare memory cells arranged in the one row. Each of the row decoders comprises a link element which can be melted by a laser beam. A plurality of decoder state determining logical circuits are provided corresponding to the plurality of row decoders. If and when a defective memory cell exists of the memory cells arranged in one row corresponding to each of the row decoders, the link element in the row decoder is melted in advance. When the row decoder having the link element melted in advance is selected by address signals, a corresponding decoder state determining logical circuit generates an SEE signal. The spare decoder is selected in place of the row decoder by the SEE signal.

Abstract: In a semiconductor memory device capable of nibble mode operation, the time period required from the time when CAS signal falls to the time when a data output buffer activating signal rises is made different at the time of a normal mode and at the time of a nibble mode, so that the time period required for reading out data in the nibble mode is reduced as compared with a conventional device.

Abstract: A semiconductor memory device includes a plurality of operation mode control circuits provided on a memory chip of the device for respectively executing a corresponding plurality of writing/reading operation modes including at least a static column mode, a high speed page mode and a nibble mode, and a plurality of operation mode selection circuits provided on the memory chip, each of the operation mode selection circuits having a fuse element and a bonding pad for selecting one of the plurality of the operation mode control circuits when the fuse element is cut off or the bonding pad is selectively wired, so that various functions can be selectively effected on the same chip.

Abstract: In the semiconductor memory device according to the present invention, a n type drain diffused region (9a) to be connected to a bit line (12) is formed on a p type semiconductor substrate (1) and a n type source diffused region (9b) is formed with a prescribed spacing from the n type drain region (9a). On the p type silicon substrate (1), a p type diffused region (16a) of high impurity density and p type diffused region (16b) of high impurity density are formed in such a manner that they are in contact with the n type drain diffused region (9a) and the n type source diffused region (9b), respectively, but not in the channel region of the n channel MOS transistor (18). Consequently, the .alpha. particle-generated charges can be decreased without changing the threshold voltage of the transfer gate transistor.

Abstract: A dynamic random access memory device having common signal lines to transmit row address signals and column address signals, uses change-over switches to transfer those signals to a row decoder. Voltage suppression circuitry limits high voltage applied to decoupling transistors provided at decoder outputs. An MOS transistor used as a voltage suppression device between the decoupling transistor and a word line activating transistor transfers word line activating signals.

Abstract: A MOS dynamic type RAM comprises memory cells (10), dummy cells (11), bit line pairs (BL, BL), word lines (WL), dummy word lines (DWL) and sense amplifiers (12). In a non-active cycle, the potentials of each pair of bit lines (BL, BL) are precharged at 1/2 of a supply potential V.sub.CC. Each sense amplifier (12) operates in an active cycle following the non-active cycle, while each active pull-up circuit (13) pulls up the potential of a higher level one of the pair of bit lines to V.sub.CC. This active cycle is defined by an internal RAS internal signal, which is generated by a NAND circuit (27) in response to an external RAS signal and an RPW signal obtained by delaying the external RAS signal by a delay circuit (20) and having a trailing edge obtained by delaying the trailing edge of the external RAS signal by a prescribed period.

Abstract: A semiconductor device formed on a semiconductor chip (1) comprises a plurality of first bonding pads (3a, 3d) for receiving an identical external signal, an internal circuit (8) connected to any one of the plurality of the first bonding pads, a second bonding pad (11) for receiving a control signal from outside the semiconductor chip, and a bonding pad selection switch (19) for selecting a bonding pad out of the plurality of first bonding pads and connecting it to the internal circuit in response to the control signal supplied thereto through the second bonding pad.

Abstract: A dynamic type MOS-RAM constructed of folded type bit lines and having sense operation cycles for amplifying potential difference appearing on respective pairs of bit lines after selection of a word line and restore operation cycles for further amplifying the potential difference on the pairs of bit lines after the sense operation cycles, wherein non-selected word lines are completely brought into electrically floating states in intervals including the sense operation cycles and the restore operation cycles.

Abstract: Each of the memory cells forming a nonvolatile RAM comprises one floating-gate transistor and one capacitor. When the power source is turned on, storage of information is performed according to the amount of electric charge stored in each capacitor. When the power source is turned off, nonvolatile storage of information is performed according to the level of the threshold voltage of each floating-gate transistor.

Abstract: A dummy word line driving circuit for a MOS dynamic RAM comprises a dummy word line controller connected to each end of a pair of dummy word lines. A sub-decode signal which is opposite to the one inputted to a dummy word driver and a dummy set signal for writing a bit line information into a not-selected dummy cell are inputted to the dummy word line controller. Means for applying a dummy equalizing signal is connected to two full-sized dummy cells, for equalizing the two before the dummy word line is driven. The two full-sized dummy cells are equalized by the signal, resulting in a charge amount, which is to be a reference value, of a half of a full-sized memory cell.

Abstract: 44Gate potentials of transistors Q.sub.R0 and Q.sub.R1 provided in an active pull-up circuit APo are always controlled to be appropriate values by a clock signal .phi..sub.p. As a result, reverse flow of electric charge from a capacitor C.sub.R0 or C.sub.R1 to a bit line LB or BL can be prevented and unfavorable influence due to such reverse flow of electric charge can be avoided in operation of the active pull-up circuit APo.

Abstract: A dynamic RAM has dummy capacitors (C6, C7) having the same capacitance as a memory capacitor connected to a pair of bit lines (BL1, BL1), respectively. During an active period, respective dummy capacitors (C6, C7) are charged to the H level and L level, which are signal levels of the bit lines (BL1, BL1) and during precharge period, both dummy capacitors are equalized. Since both dummy capacitors (C6, C7) respectively connected to a pair of bit lines (BL1, BL1) are equalized during precharge period, so that the stored charge values of the dummy capacitors (C6, C7) both become the intermediate value of the ground level and supply potential level.

Abstract: A semiconductor memory device comprises a data input switching circuit (20) connected between the output side of a write check bit generating circuit (2) and the input side of a check bit memory cell array (32), a data output switching circuit (30) connected to the input side of an address decoder (9), and an address switching circuit (10) connected to the output side of the address decoder (9). When a test mode is entered, the data input switching circuit (2), data output switching circuit (30) and address switching circuit (10) connect a data input signal line (l), data output signal line (m) and address signal line (n), respectively, to the check bit memory cell array (32), enabling the check bit memory cell array (32) to be accessed from the outside.