Abstract: A semiconductor readout circuit includes a precharge circuit which charges a bit line connected to a memory cell to its predetermined precharge voltage before reading out information stored in the memory cell, a feedback-type bias circuit which controls a voltage of the bit line to its predetermined voltage, a sense amplifier which detects and amplifies a change in a voltage of a readout input node connected to the bit line via a transfer gate of the feedback-type bias circuit, and a load circuit which charges the readout input node. The load circuit is made inactive at least for a fixed period immediately before ending of a precharge period when the precharge circuit is active, and is made active after ending of the precharge period.

Abstract: A semiconductor memory device including: a memory cell array in which memory cells are arranged; a plurality of terminals for accepting commands issued by an external user; a command interface circuit for interfacing between the external user and the memory cell array; a write state machine for controlling the programming and erasing operations; and an output circuit for outputting an internal signal to the plurality of terminals, wherein the memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional elements formed on both sides of the gate electrode and having the function of retaining charges.

Abstract: A memory cell array is included which is constituted by arranging the plurality of nonvolatile memory cells in a row direction and column direction respectively and arranging the plurality of word lines (WL) and the plurality of bit lines (BL) in the row direction and the column direction respectively in order to select a predetermined memory cell or a memory cell group out of the arranged nonvolatile memory cells, in which the memory cells are respectively constituted by connecting one end of a variable resistive element for storing information in accordance with a change of electrical resistances with the source of a selection transistor while in the memory cell array, the drain of the selection transistor is connected with a common bit line (BL) along the column direction, the other end of the variable resistive element is connected with a source line (SL), and the gate of the selection transistor is connected with the common word line (WL) along the row direction.

Abstract: A semiconductor memory device includes a control logic circuit for generating read selection signals each selecting one plane for reading and write selection signals each selecting one plane for writing from a plurality of planes in which memory cells are arranged in an array, an address selection circuit disposed for each of the planes, and an address buffer circuit for simultaneously providing a write address and a read address. Each of the address selection circuits is configured so as to be able to receive one of the read selection signals and one of the write selection signals from the control logic circuit.

Abstract: A semiconductor storage device includes a memory cell array 21 in which a plurality of memory elements are arranged and a program verify circuit 30. The memory element 1, 33 includes a gate electrode 104 formed on a semiconductor layer 102 via a gate insulator 103, a channel region arranged below the gate electrode 104, diffusion regions 107a, 107b that are located on opposite sides of the channel region and have a conductive type opposite to that of the channel region, and memory function bodies 109 that are located on opposite sides of the gate electrode 104 and have a function of retaining electric charge. A program load register 32 of the program verify circuit 30 eliminates a state that a memory element 33 which has initially been verified as having been correctly programmed needs to be further programmed.

Abstract: A method for driving a semiconductor memory device includes a memory array having a plurality of memory cells arranged in rows and columns. Each memory cell includes a gate electrode formed on a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, a source and a drain as diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional units formed on both sides of the gate electrode and having a function of retaining charges. The method includes the steps of: selecting a row line connected to the gate electrode of a memory cell to be selected; grounding a first column line connected to the source of the memory cell to be selected; and applying a first potential to a second column line and a second potential to a third column line at the same time.

Abstract: A method of verifying programming of a nonvolatile memory cell to a desired state, the method comprising the steps of: selecting first and second references respectively corresponding to first and second voltages; applying a programming voltage to the memory cell; sensing a threshold voltage level of the memory cell; and comparing the sensed threshold voltage level with the first and second references and, in the case where the threshold voltage level is higher than the first reference and lower than the second reference, indicating that the memory cell is programmed into the desired state, wherein the nonvolatile memory cell includes a gate electrode formed on a semiconductor layer via a gate insulating film, a channel region formed below the gate electrode, a source and a drain as diffusion regions formed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional units formed on both sides of the gate electrode and having the function of re

Abstract: A semiconductor storage device is provided with a gate electrode, a semiconductor layer, a gate insulating film sandwiched between the gate electrode and the semiconductor layer, a channel region under the gate electrode, diffusion regions provided respectively on two sides of the channel regions and being of the other conductivity region than the channel region, memory elements 1 provided respectively on two sides of the gate electrode and having a function of holding charges, and a word line driver circuit, in which the CMOS technique is used. The driver circuit includes a common node for supplying a potential for activating an output inverter for driving a row word line. While the semiconductor storage device is in a read mode, a CMOS inverter other than the output inverter controls a signal at the common node, the CMOS inverter connected to a read input line.

Abstract: A semiconductor memory device includes a memory cell array in which plural memory cells are arranged, a memory operation circuit, connected to the memory cell array, for executing a memory operation on the memory cell array, and a command controller, connected to the memory operation circuit, for receiving a command from the outside and generating a predetermined control signal to the memory operation circuit on the basis of the received command to control execution of the memory operation by the memory operation circuit. The memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional units formed on both sides of the gate electrode and having the function of retaining charges.

Abstract: A semiconductor memory device of the present invention includes an electrically programmable and erasable nonvolatile memory device which uses a plurality of memory cells requiring a first potential for reading data and a second potential for data programming, the second potential being higher than the first potential, a latch circuit for receiving data and temporarily storing the data, a pulse generator which generates a pulse used for programming data into a memory cell and is coupled in order to receive the second potential, a comparator for comparing data in the latch circuit with data in a memory cell, and a controller for controlling the pulse generator to repeatedly generate a pulse until the data in the latch circuit matches the data in the memory cell, the controller coupled to the comparator and the pulse generator. The controller controls so that the pulse is repeatedly generated until data is programmed in a memory cell.

Abstract: A semiconductor memory device has a malfunction prevention device and a nonvolatile memory. The nonvolatile memory is a memory cell including: a gate electrode formed on a semiconductor layer via a gate insulating film; a channel region disposed below the gate electrode; diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region; and memory functional units formed on both sides of the gate electrode and having a function of retaining charges.

Abstract: A reading circuit for reading information stored in a memory cell includes a current supply circuit for supplying a current to a bit line connected to the memory cell; a comparison circuit for comparing a potential of the bit line supplied with the current by the current supply circuit with a reference potential so as to output the information stored in the memory cell; a disconnection circuit for electrically disconnecting the comparison circuit and the memory cell from each other under a prescribed condition; a charge circuit for charging the bit line, the charge circuit stopping charging of the bit line when the potential of the bit line exceeds a prescribed potential; and a discharge circuit for discharging the bit line when the potential of the bit line exceeds the prescribed potential.

Abstract: It is an object of the present invention to make it possible to decrease the on-state resistance of a selection transistor of a memory cell without increasing the whole area of a memory cell array and accelerate and stabilize the reading operation of data stored in the memory cell. Therefore, a plurality of variable resistive elements capable of storing information in accordance with a change of electrical resistances is included, one ends of the variable resistive elements are connected each other, and an electrode of a selection element constituted by a MOSFET or diode element for selecting the variable resistive elements in common is connected with one end of each of the variable resistive elements to constitute a memory cell.

Abstract: A semiconductor memory device comprises a column readout voltage supply circuit which supplies a predetermined first voltage when readout is selected and supplies a predetermined second voltage which is different from the fist voltage when the readout is not selected, to each column selection line, a row readout voltage supply circuit which supplies the second voltage to each row selection line at the time of readout, a sense circuit which detects a current flowing in the selected row selection line separately from a current flowing in the non-selected row selection lines to detect an electric resistance state of the selected memory cell at the time of readout, and a column voltage displacement prevention circuit which prevents displacement of a supplied voltage level for each of the non-selected column selection lines at the time of readout.

Abstract: A semiconductor readout circuit according to the present invention includes a precharge circuit which charges a bit line connected to a memory cell to its predetermined precharge voltage before reading out information stored in the memory cell, a feedback-type bias circuit which controls a voltage of the bit line to its predetermined voltage, a sense amplifier which detects and amplifies a change in a voltage of a readout input node connected to the bit line via a transfer gate of the feedback-type bias circuit, and a load circuit which charges the readout input node. The load circuit is made inactive at least for a fixed period immediately before ending of a precharge period when the precharge circuit is active, and is made active after ending of the precharge period.

Abstract: The present invention prevents a reading operation margin from being decreased due to a current injected into a selected bit line after passing through an unselected bit line in a memory cell array configuration using virtual ground lines. A memory cell array is constituted by being divided into at least subarrays of a plurality of columns and memory cell columns at the both ends of the subarrays are constituted so that second electrodes are not connected each other but they are separated from each other between two memory cells adjacent to each other in the row direction at the both sides of boundaries between the subarrays and respectively connected to an independent bit line or virtual ground line, and one of word lines, one of bit lines, and one of virtual ground lines are selected and one memory cell from which data will be read is selected.

Abstract: The present invention provides a method of programming, into a computer, a memory array having a plurality of memory cells, including a verification step 1 of verifying whether a memory cell has been already programmed or it has not been programmed yet per memory cell to be programmed, a flagging step 2 of flagging the memory cell in the case where it is verified that the memory cell has not been programmed yet in the several verifying steps, to which the memory cell is subjected thereafter, even if it is verified that the memory cell has been already programmed, a first application step 3 of applying a programming pulse having a programming level to the not-programmed memory cell without any flag, a repeat step 4 of repeating the verification step 1, the flagging step 2 and the first application step 3 until it is verified that all of the memory cells have been already programmed at least once, and a second application step 5 of applying a boost pulse having a boost programming level lower than that of the p

Abstract: A semiconductor memory device includes a first nonvolatile memory cell, a bit line connected to the first nonvolatile memory cell, and a control circuit connected to the first nonvolatile memory cell and the bit line, and disposed and configured in such a manner as to reset the bit line to a predetermined first potential state only for a certain period “a” of time in response to transition of an input address signal. The first nonvolatile memory cell has a gate electrode formed on a semiconductor layer via a gate insulating film; a channel region disposed under the gate electrode; diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region; and memory functional units formed on both sides of the gate electrode and having the function of retaining charges.

Abstract: The present invention provides a semiconductor memory device including a memory cell array in which a plurality of memory cells are arranged, a user interface circuit including a command queue having a logic circuit for accepting commands issued by an external user and generating a program memory address, and an array control circuit having a microcontroller and a program memory for storing therein an execution code, and executing an operation on the memory cell array, wherein the memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional elements formed on both sides of the gate electrode and having the function of retaining charges.

Abstract: A semiconductor storage device includes a memory cell array 21 in which a plurality of memory elements are arranged and a program verify circuit 30. The memory element 1, 33 includes a gate electrode 104 formed on a semiconductor layer 102 via a gate insulator 103, a channel region arranged below the gate electrode 104, diffusion regions 107a, 107b that are located on opposite sides of the channel region and have a conductive type opposite to that of the channel region, and memory function bodies 109 that are located on opposite sides of the gate electrode 104 and have a function of retaining electric charge. A program load register 32 of the program verify circuit 30 eliminates a state that a memory element 33 which has initially been verified as having been correctly programmed needs to be further programmed.