Abstract: An electrically erasable programmable read-only memory with a NAND cell structure has parallel bit lines, and memory cells defining NAND cell blocks, each of which has a series-circuit of memory cell transistors. Each transistor has a floating gate and a control gate. Parallel word lines are connected to the control gates of the cell transistors. The first, second and third intermediate voltages are used in the data write mode: the first voltage is lower than the "H" level voltage and higher than the "L" level voltage; the second and third voltages are higher than the first voltage and lower than the "H" level voltage.

Abstract: A semiconductor memory device includes a plurality of memory cells each having a bipolar transistor whose collector-emitter voltage V.sub.CE is controlled according to the base potential to satisfy the condition of I.sub.BE <I.sub.CB when the forward base current in the base-emitter path and the reverse base current in the collector-base path are respectively expressed by I.sub.BE and I.sub.CB and a switching element connected to the bipolar transistor, word lines, bit lines and emitter electrode lines connected to the memory cells, and functions as a dynamic memory cell in the data storing operation and as a gain memory cell in the readout operation.

Abstract: A semiconductor memory device comprises a memory array including a plurality of memory cells arranged in a matrix form, a plurality of word lines arranged in column and a plurality of bit lines arranged in row. Each memory cell includes a bipolar transistor in which a collector-emitter voltage is controlled so that the polarity of a base current changes is changed in accordance with an increase in a base-emitter voltage, and a switching element, provided between the base of the bipolar transistor and an associated bit line and controllable by an associated word line. A switch circuit is provided for applying a collector voltage to the collector of the bipolar transistor smaller in a second state where an associated one of the memory cells is holding data than in a second state where the associated memory cell is accessible for data reading and data writing.

Abstract: An electrically erasable programmable read-only memory with a NAND cell structure has parallel bit lines, and memory cells defining NAND cell blocks, each of which has a series-circuit of memory cell transistors. Each transistor has a floating gate and a control gate. Parallel word lines are connected to the control gates of the cell transistors. The first, second and third intermediate voltages are used in the data write mode: the first voltage is lower than the "H" level voltage and higher than the "L" level voltage; the second and third voltages are higher than the first voltage and lower than the "H" level voltage.

Abstract: A semiconductor device includes a rectangular semiconductor chip, first to fourth memory cell arrays formed on the semiconductor chip, and first to fourth bonding pads formed on the peripheral part of the semiconductor chip. In this semiconductor device in particular, first bonding pads are disposed along a first long side of the semiconductor chip while second bonding pads are disposed along a second long side of the chip. The first and second memory cell arrays are disposed between the first bonding pads and the second long side while the third and fourth memory cell arrays are disposed between the first long side and the second pads.

Abstract: A divided-bit line type dynamic random-access memory is disclosed which has parallel main bit line pairs in each of which sub-bit line pairs are provided to be electrically parallel with each other. Parallel word lines are provided on the substrate to insulatively cross the sub-bit line pairs. Memory cells are connected to crossing points of the sub-bit line pairs and the word lines. Main sense amplifiers are respectively connected to the main bit line pairs, sub-sense amplifiers are respectively connected to the sub-bit line pairs. A specific refreshing technique is utilized, according to which, when a refreshing operation is executed in a refreshing mode of the memory, the same number of word lines as that of sub-bit line pairs provided in each main-bit line pair are simultaneously selected, and the sub-sense amplifiers are activated to refresh together the memory cells which are connected to the work lines thus selected.

Abstract: A dynamic random access memory including a sense amplifier having MOSFETs, which constitute a flip-flop, and an activating MOSFET. A memory cell includes a switching MOSFET and a capacitor having a grooved structure. A dummy cell includes a switching MOSFET and capacitor having a planar structure. The activating MOSFET has its gate coupled to a gate bias generator, which comprises a reference capacitor group consisting of planar type capacitors having a nearly constant capacitance, irrespective of the influence of process parameters, and a monitoring capacitor group consisting of capacitors having the same grooved structure and the same capacitance as the memory cell capacitor. The reference capacitor group, and the monitoring capacitor group are pre-charged. When the sensing operation starts, the reference capacitor group and the monitoring capacitor group are short-circuited, so that a charge reallocation is executed between these groups.

Abstract: A dynamic random access memory system comprises first and second memory banks. A plurality of memory cells connected to a word line are grouped into first and second groups. The first group is arranged in the first memory bank and the second group is arranged in the second memory bank. Read/write means is provided in which each n bits from and to the first group and each n bits from and to the second group are read and written alternatively. Each bit is read and written in synchronism with the toggles of a column address strobe signal.

Abstract: A word line driver for use in a dRAM. This word line driver comprises one npn bipolar transistor and four n-channel transistors. The bipolar transistor is connected between an "H"-level potential terminal and an output terminal. The first MOS transistor is connected in parallel to the bipolar transistor, and is driven by one output signal of a row decoder to supply an output at a sufficiently high "H" level to word lines. The third MOS transistor is coupled between the base and collector of the bipolar transistor, and its gate is connected to the gate of the first MOS transistor. The third MOS transistor supplies a sufficient base current to the base of the bipolar transistor when the word line driver outputs a potential at the "H" level. The second MOS transistor is coupled between the source of the first MOS transistor and a ground potential terminal, and the fourth MOS transistor is coupled between the source of the third MOS transistor and the ground potential terminal.

Abstract: There is disclosed a divided-bit line type dynamic random access memory having parallel main bit line pairs which are formed on a substrate and to each of which sub-bit line pairs are provided in parallel with each other. Parallel word lines insulatively cross the sub-bit line pairs. Memory cells are provided at the crossing points of the sub-bit line pairs and the word lines. Each memory cell has a capacitor for storing information and a voltage-controlled switching transistor such as a MOSFET. First sense amplifier circuits are connected to the sub-bit line pairs, while second sense amplifier circuits are connected to the main bit line pairs. In a restoring mode, a specific sub-bit line pair, to which a selected memory cell is connected, is electrically disconnected from the corresponding main bit one pair, and a first sense amplifier circuit connected thereto is activated to perform a restoring operation.

Abstract: A semiconductor memory device has N sense amplifiers each having first and second input terminals, N first memory cells, N second memory cells, N first bit lines each of which is connected to the first memory cells of the same column and connected to the first input terminal of one of the sense amplifiers, and N second bit lines each of which is connected to the second memory cells of the same column and connected to the second input terminal of one of the sense amplifiers. The first memory cells are formed in a first memory cell area and the second memory cells are formed in a second memory cell area arranged adjacent to the first memory cell area and on the same side as the first memory cell area with respect to the sense amplifiers.

Abstract: A semiconductor memory device and a method for manufacturing such a device provides increased capacitance for memory cells of a dynamic RAM by using the top and sides of island regions formed in the substrate.

Abstract: A semiconductor nonvolatile read only memory device has a voltage applying circuit which sets all word lines at ground potential in a stand-by mode and sets only a selected word line at a high level in an active mode. The word lines are connected to the gates of semiconductor nonvolatile memory transistors. Each of the memory transistors has the source (or drain) grounded and the drain (or source) connected to output lines. In a stand-by mode, the voltage applying circuit keeps all the word lines at ground potential. In an active mode, the voltage applying circuit applies a high level voltage only to the selected word line. The memory transistor connected to the selected word line produces data of "0" or "1" to the output line.

Abstract: A nonvolatile read only memory detects a time varying change of the amount of data written in the memory cell transistor using a circuit for supplying a constant potential which is higher than the threshold voltage of a reference cell transistor and which is independent of a power source voltage used for reading out connected to the gate of the reference cell transistor.