摘要:
According to one embodiment, a semiconductor memory device includes a memory cell array includes a plurality of memory cell units which are arranged at intersections of a plurality of bit lines and a plurality of word lines and whose current paths are connected in series, a voltage generator circuit which generates a voltage to be applied to the memory cell array, and a control circuit which controls the memory cell array and the voltage generator circuit. The control circuit, when writing data into the memory cell array, performs control so as to apply a first write pass voltage to unselected word lines in the memory cell units and, after a selected word line has reached a write voltage, further apply a voltage to the unselected word lines until a second write pass voltage higher than the first write pass voltage has been reached.
摘要:
A nonvolatile semiconductor memory device in accordance with an embodiment includes: a memory cell array having electrically rewritable nonvolatile memory cells; and a control unit. The control unit performs control of repeating a write operation, a write verify operation, and a step-up operation, the write verify operation being an operation to verify whether data write is completed or not, and the step-up operation being an operation to raise the write pulse voltage if data write is not completed. The control unit, during the write operation, raises a first write pulse voltage with a first gradient, and then raises a second write pulse voltage with a second gradient, thereby executing the write operation, the first write pulse voltage including at least a write pulse voltage generated at first, the second write pulse voltage being generated after the first write pulse voltage, and the second gradient being larger than the first gradient.
摘要:
For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
摘要:
A non-volatile semiconductor memory device according to one embodiment of the present invention includes a memory cell array and a control unit. The control unit is configured to control a repeat of an erase operation, an erase verify operation, and a step-up operation. The control unit is configured to perform a soft-programming operation of setting the memory cells from an over-erased state to a first threshold voltage distribution state when, in a series of erase operations, the number of erase voltage applications is more than a first number and less than a second number (the first number
摘要:
A semiconductor storage device has a plurality of memory cells each having a control gate that are formed on a well. The semiconductor storage device has a control circuit that applies a voltage to the well and the control gates.In an erase operation of the memory cell, the control circuit applies a first pulse wave of a first erasure voltage that rises stepwise to the well and then applies a second pulse wave of a second erasure voltage to the well.
摘要:
For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
摘要:
A nonvolatile semiconductor memory device in accordance with an embodiment includes: a memory cell array having electrically rewritable nonvolatile memory cells; and a control unit. The control unit performs control of repeating a write operation, a write verify operation, and a step-up operation, the write verify operation being an operation to verify whether data write is completed or not, and the step-up operation being an operation to raise the write pulse voltage if data write is not completed. The control unit, during the write operation, raises a first write pulse voltage with a first gradient, and then raises a second write pulse voltage with a second gradient, thereby executing the write operation, the first write pulse voltage including at least a write pulse voltage generated at first, the second write pulse voltage being generated after the first write pulse voltage, and the second gradient being larger than the first gradient.
摘要:
A non-volatile semiconductor memory device according to one embodiment includes: a cell array; and a data writing unit that repeatedly executes a write loop including a programming operation of applying a program voltage to a selected word line and a passage voltage to non-selected word lines during writing of data, in which, when a difference between the passage voltage used in an n-th write loop and the passage voltage used in an n+1-th write loop is expressed as ΔVn and when a condition of L
摘要:
According to one embodiment, a semiconductor memory device includes a memory cell array includes a plurality of cell units each composed of a plurality of memory cells which are arranged at intersections of a plurality of bit lines and a plurality of word lines and whose current paths are connected in series and select transistors each connected to either end of the series connection, a voltage generator circuit which generates a voltage applied to the memory cell array, and a control circuit which controls the memory cell array and the voltage generator circuit.
摘要:
A non-volatile semiconductor memory device according to one embodiment of the present invention includes a memory cell array and a control unit. The control unit is configured to control a repeat of an erase operation, an erase verify operation, and a step-up operation. The control unit is configured to perform a soft-programming operation of setting the memory cells from an over-erased state to a first threshold voltage distribution state when, in a series of erase operations, the number of erase voltage applications is more than a first number and less than a second number (the first number