摘要:
There is provided a method of programming a non-volatile memory which can solve the problem of the data write system of the existing flash memory that a load capacitance of bit lines becomes large, the time required by the bit lines to reach the predetermined potential becomes longer, thereby the time required for data write operation becomes longer and power consumption also becomes large because the more the memory capacitance of memory array increases, the longer the length of bit lines becomes and the more the number of bit lines increases. In the non-volatile memory of the invention comprising the AND type memory array in which a plurality of memory cells are connected in parallel between the local bit lines and local drain lines, the local drain lines are precharged by supplying thereto a comparatively higher voltage from the common drain line side (opposite side of the main bit lines), the main bit lines are selectively precharged by applying thereto the voltage of 0V or a comparatively small voltage depending on the write data and thereafter a drain current is applied only to the selected memory cells to which data is written by applying the write voltage to the word lines in order to implant the hot electrons to the floating gate.
摘要:
A nonvolatile semiconductor memory device capable of realizing optimized erasing operation in a memory array configuration in which a plurality of pages correspond to and are connected to each of a plurality of word lines and higher speed of the erasing operation. In a flash memory, the erasing operation is performed by an erasing method of erasing a plurality of pages arbitrarily selected in a lump. In a two-page erasing mode, page erasure, page pre-erasure verification, page rewriting process, page pre-rewriting verification, and page upper end determining process are performed in order. The method realizes, particularly, (1) suppression of the number of erase verification times to the minimum by performing erase verification only on arbitrary one even-numbered or odd-numbered page in the pages to be erased in consideration of variations in the erasing characteristic, and (2) prevention of erroneous determination of the upper end of erasure since it is unnecessary to set a memory cell to be rewritten every rewrite verification by continuously executing the rewriting process page by page.
摘要:
There is provided a method of programming a non-volatile memory which can solve the problem of the data write system of the existing flash memory that a load capacitance of bit lines becomes large, the time required by the bit lines to reach the predetermined potential becomes longer, thereby the time required for data write operation becomes longer and power consumption also becomes large because the more the memory capacitance of memory array increases, the longer the length of bit lines becomes and the more the number of bit lines increases. In the non-volatile memory of the invention comprising the AND type memory array in which a plurality of memory cells are connected in parallel between the local bit lines and local drain lines, the local drain lines are precharged by supplying thereto a comparatively higher voltage from the common drain line side (opposite side of the main bit lines), the main bit lines are selectively precharged by applying thereto the voltage of 0V or a comparatively small voltage depending on the write data and thereafter a drain current is applied only to the selected memory cells to which data is written by applying the write voltage to the word lines in order to implant the hot electrons to the floating gate.
摘要:
A nonvolatile semiconductor memory device capable of realizing optimized erasing operation in a memory array configuration in which a plurality of pages correspond to and are connected to each of a plurality of word lines and higher speed of the erasing operation. In a flash memory, the erasing operation is performed by an erasing method of erasing a plurality of pages arbitrarily selected in a lump. In a two-page erasing mode, page erasure, page pre-erasure verification, page rewriting process, page pre-rewriting verification, and page upper end determining process are performed in order. The method realizes, particularly, (1) suppression of the number of erase verification times to the minimum by performing erase verification only on arbitrary one even-numbered or odd-numbered page in the pages to be erased in consideration of variations in the erasing characteristic, and (2) prevention of erroneous determination of the upper end of erasure since it is unnecessary to set a memory cell to be rewritten every rewrite verification by continuously executing the rewriting process page by page.
摘要:
There is provided a method of programming a non-volatile memory which can solve the problem of the data write system of the existing flash memory that a load capacitance of bit lines becomes large, the time required by the bit lines to reach the predetermined potential becomes longer, thereby the time required for data write operation becomes longer and power consumption also becomes large because the more the memory capacitance of memory array increases, the longer the length of bit lines becomes and the more the number of bit lines increases. In the non-volatile memory of the invention comprising the AND type memory array in which a plurality of memory cells are connected in parallel between the local bit lines and local drain lines, the local drain lines are precharged by supplying thereto a comparatively higher voltage from the common drain line side (opposite side of the main bit lines), the main bit lines are selectively precharged by applying thereto the voltage of 0V or a comparatively small voltage depending on the write data and thereafter a drain current is applied only to the selected memory cells to which data is written by applying the write voltage to the word lines in order to implant the hot electrons to the floating gate.
摘要:
A nonvolatile semiconductor memory device capable of realizing optimized erasing operation in a memory array configuration in which a plurality of pages correspond to and are connected to each of a plurality of word lines and higher speed of the erasing operation. In a flash memory, the erasing operation is performed by an erasing method of erasing a plurality of pages arbitrarily selected in a lump. In a two-page erasing mode, page erasure, page pre-erasure verification, page rewriting process, page pre-rewriting verification, and page upper end determining process are performed in order. The method realizes, particularly, (1) suppression of the number of erase verification times to the minimum by performing erase verification only on arbitrary one even-numbered or odd-numbered page in the pages to be erased in consideration of variations in the erasing characteristic, and (2) prevention of erroneous determination of the upper end of erasure since it is unnecessary to set a memory cell to be rewritten every rewrite verification by continuously executing the rewriting process page by page.
摘要:
A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.
摘要:
A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.
摘要:
A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.
摘要:
A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.