Patents by Inventor Tetsuya Tsujikawa
Tetsuya Tsujikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20020080649Abstract: In a nonvolatile semiconductor memory device in which a plurality of threshold values are set to store multi-level data in a memory cell, bits of multi-bit data are separately written into a memory cell according to an address signal or a control signal to effect the reading and erasing. Concretely, the memory array is so constituted that it can be accessed by three-dimensional address of X, Y and Z, and multi-bit data in the memory cell is discriminated by the Z-address.Type: ApplicationFiled: December 21, 2001Publication date: June 27, 2002Inventors: Naoki Yamada, Hiroshi Sato, Tetsuya Tsujikawa, Kazuyuki Miyazawa
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Publication number: 20020044485Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: ApplicationFiled: December 11, 2001Publication date: April 18, 2002Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Publication number: 20020027807Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: ApplicationFiled: November 1, 2001Publication date: March 7, 2002Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Publication number: 20020008991Abstract: Data are generated based on additional write data input to data latch circuits (DLR and DLL) and data read from memory cells (MC) to program non-volatile memory cells in a write state into the same write state and to program non-volatile memory cells in an erase state into a write state indicated by the additional write data. The generated data are latched in the data latch circuits to perform a logical synthesis process for additional writing. Even after the additional write operation, the logically synthesized data remain in the data latch circuits, and the latched data can be reused against abnormality in writing. This eliminates the need for receiving write data again from the outside when the additional write operation is to be retried.Type: ApplicationFiled: October 1, 2001Publication date: January 24, 2002Inventors: Michitaro Kanamitsu, Tetsuya Tsujikawa, Toshinori Harada, Hiroaki Kotani, Shoji Kubono, Atsushi Nozoe, Takayuki Yoshitake
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Publication number: 20020001231Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell-is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: ApplicationFiled: March 30, 2000Publication date: January 3, 2002Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamaoto, Ken Matsubara
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Patent number: 6335878Abstract: In a nonvolatile semiconductor memory device in which a plurality of threshold values are set to store multi-level data in a memory cell, bits of multi-bit data are separately written into a memory cell according to an address signal or a control signal to effect the reading and erasing. Concretely, the memory array is so constituted that it can be accessed by three-dimensional address of X, Y and Z, and multi-bit data in the memory cell is discriminated by the Z-address.Type: GrantFiled: November 7, 2000Date of Patent: January 1, 2002Assignee: Hitachi, Ltd.Inventors: Naoki Yamada, Hiroshi Sato, Tetsuya Tsujikawa, Kazuyuki Miyazawa
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Patent number: 6333871Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: GrantFiled: March 30, 2000Date of Patent: December 25, 2001Assignee: Hitachi, Ltd.Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Patent number: 6320793Abstract: A non-volatile memory device having a plurality of memory cells and a control circuit. The control circuit receives operation commands from outside the device and controls the operation of the device according to the commands. The commands include read commands and write commands. In the read command the control circuit reads data in the memory cells and outputs it. In a write command the control circuit controls the inputting of data to data latch circuits and then to memory cells. The control circuit provides status information indicating whether the writing of data is a success or a failure.Type: GrantFiled: March 30, 2001Date of Patent: November 20, 2001Assignee: Hitachi, Ltd.Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Patent number: 6301150Abstract: Data are generated based on additional write data input to data latch circuits (DLR and DLL) and data read from memory cells (MC) to program non-volatile memory cells in a write state into the same write state and to program non-volatile memory cells in an erase state into a write state indicated by the additional write data. The generated data are latched in the data latch circuits to perform a logical synthesis process for additional writing. Even after the additional write operation, the logically synthesized data remain in the data latch circuits, and the latched data can be reused against abnormality in writing. This eliminates the need for receiving write data again from the outside when the additional write operation is to be retried.Type: GrantFiled: April 28, 2000Date of Patent: October 9, 2001Assignee: Hitachi, Ltd.Inventors: Michitaro Kanamitsu, Tetsuya Tsujikawa, Toshinori Harada, Hiroaki Kotani, Shoji Kubono, Atsushi Nozoe, Takayuki Yoshitake
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Publication number: 20010010644Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: ApplicationFiled: March 30, 2001Publication date: August 2, 2001Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Publication number: 20010009520Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the over programming condition, the program data is no longer required to be again received from the external device.Type: ApplicationFiled: March 30, 2001Publication date: July 26, 2001Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Patent number: 6233174Abstract: A nonvolatile semiconductor memory device having a plurality of memory cells. Each cell stores data and has a threshold voltage corresponding to the data. A controller controls a partial erase operation in response to a command. This operation includes selecting memory cells in two groups, storing the data in a data latch, writing erase data indicating an erase state, erasing data of selected cells and programming the data stored in the data latch to selected memory cells and programming the erased data to selected memory cells.Type: GrantFiled: March 30, 2000Date of Patent: May 15, 2001Assignee: Hitachi, Ltd.Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Patent number: 6166950Abstract: In a nonvolatile semiconductor memory device in which a plurality of threshold values are set to store multi-level data in a memory cell, bits of multi-bit data are separately written into a memory cell according to an address signal or a control signal to effect the reading and erasing. Concretely, the memory array is so constituted that it can be accessed by three-dimensional address of X, Y and Z, and multi-bit data in the memory cell is discriminated by the Z-address.Type: GrantFiled: July 28, 1998Date of Patent: December 26, 2000Assignee: Hitachi, Ltd.Inventors: Naoki Yamada, Hiroshi Sato, Tetsuya Tsujikawa, Kazuyuki Miyazawa
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Patent number: 6078519Abstract: Data are generated based on additional write data input to data latch circuits (DLR and DLL) and data read from memory cells (MC) to program non-volatile memory cells in a write state into the same write state and to program non-volatile memory cells in an erase state into a write state indicated by the additional write data. The generated data are latched in the data latch circuits to perform a logical synthesis process for additional writing. Even after the additional write operation, the logically synthesized data remain in the data latch circuits, and the latched data can be reused against abnormality in writing. This eliminates the need for receiving write data again from the outside when the additional write operation is to be retried.Type: GrantFiled: May 25, 1999Date of Patent: June 20, 2000Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.Inventors: Michitaro Kanamitsu, Tetsuya Tsujikawa, Toshinori Harada, Hiroaki Kotani, Shoji Kubono, Atsushi Nozoe, Takayuki Yoshitake
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Patent number: 6046936Abstract: Externally supplied program data is latched into data latch circuits DLL and DLR. A judgment is made as to whether or not the latched program data corresponds to any threshold value of multi-levels every time each of plural programing operations is carried out. The program control information corresponding to the judgment result is latched into a sense latch circuit SL. Based upon the latched program control information, the programing operation for setting threshold voltages having multi-levels to a memory cell is carried out in a stepwise manner. Even when the programing operation is ended, the externally supplied program data is left in the data latch circuit. Even when the programing operation of the memory cell is retried due to the overprograming condition, the program data is no longer required to be again received from the external device.Type: GrantFiled: February 16, 1999Date of Patent: April 4, 2000Assignee: Hitachi, Ltd.Inventors: Tetsuya Tsujikawa, Atsushi Nozoe, Michitaro Kanamitsu, Shoji Kubono, Eiji Yamamoto, Ken Matsubara
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Patent number: 5872734Abstract: A semiconductor nonvolatile memory device including transistors whose threshold voltages can be electrically rewritten (erased, written). A read-selected word line voltage Vrw, lower than the supply voltage Vcc applied from the outside, is applied, and the threshold voltage difference between the higher threshold voltage VthH and the lower threshold voltage VthL in the two states of nonvolatile memory cells is reduced to bring the higher threshold voltage VthH close to the lower threshold voltage VthL. Moreover, a threshold voltage Vthi in the thermally equilibrium state of the memory cell, corresponding to the two threshold voltages of the two states, is set between the higher threshold voltage VthH and the lower threshold voltage VthL.Type: GrantFiled: April 15, 1998Date of Patent: February 16, 1999Assignee: Hitachi, Ltd.Inventors: Toshihiro Tanaka, Masataka Kato, Katsutaka Kimura, Tetsuya Tsujikawa, Kazuyoshi Oshima, Kazuyuki Miyazawa
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Patent number: 5748532Abstract: A semiconductor nonvolatile memory device including transistors whose threshold voltages can be electrically rewritten (erased, written). A read-selected word line voltage Vrw, lower than the supply voltage Vcc applied from the outside, is applied, and the threshold voltage difference between the higher threshold voltage VthH and the lower threshold voltage VthL in the two states of the nonvolatile memory cells is reduced to bring the higher threshold voltage VthH close to the lower threshold voltage VthL. Moreover, a threshold voltage Vthi in the thermally equilibrium state of the memory cell, corresponding to the two threshold voltages of the two states, is set between the higher threshold voltage VthH and the lower threshold voltage VthL.Type: GrantFiled: July 10, 1996Date of Patent: May 5, 1998Assignee: Hitachi, Ltd.Inventors: Toshihiro Tanaka, Masataka Kato, Katsutaka Kimura, Tetsuya Tsujikawa, Kazuyoshi Oshima, Kazuyuki Miyazawa
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Patent number: 5699311Abstract: A semiconductor memory device in which a plurality of data lines of a memory array comprising storage transistors arranged in a matrix form as those having a high or low threshold voltage according to stored data are divided into a plurality of blocks, and sense amplifiers for performing amplification operations dispersedly in time are used to amplify signals. Moreover, a first and a second group of sense amplifiers corresponding to odd- and even-numbered adjoining data lines are arranged so that while the output signals of one group of sense amplifiers are output, word lines are switched, and the other group of sense amplifiers are caused to perform the operation of amplifying the signals read from the memory cells corresponding to the word lines thus switched, respectively.Type: GrantFiled: December 11, 1996Date of Patent: December 16, 1997Assignee: Hitachi, Ltd.Inventors: Hiroshi Sato, Keiichi Yoshida, Tetsuya Tsujikawa
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Patent number: 5654916Abstract: A semiconductor memory device in which a plurality of data lines of a memory array comprising storage transistors arranged in a matrix form as those having a high or low threshold voltage according to stored data are divided into a plurality of blocks, and sense amplifiers for performing amplification operations dispersedly in time are used to amplify signals. Moreover, a first and a second group of sense amplifiers corresponding to odd- and even-numbered adjoining data lines are arranged so that while the output signals of one group of sense amplifiers are output, word lines are switched, and the other group of sense amplifiers are caused to perform the operation of amplifying the signals read from the memory cells corresponding to the word lines thus switched, respectively.Type: GrantFiled: August 2, 1995Date of Patent: August 5, 1997Assignee: Hitachi, Ltd.Inventors: Hiroshi Sato, Keiichi Yoshida, Tetsuya Tsujikawa
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Patent number: 5473570Abstract: A semiconductor memory device in which a plurality of data lines of a memory array comprising storage transistors arranged in a matrix form as those having a high or low threshold voltage according to stored data are divided into a plurality of blocks, and sense amplifiers for performing amplification operations dispersedly in time are used to amplify signals. Moreover, a first and a second group of sense amplifiers corresponding to odd- and even-numbered adjoining data lines are arranged so that while the output signals of one group of sense amplifiers are output, word lines are switched, and the other group of sense amplifiers are caused to perform the operation of amplifying the signals read from the memory cells corresponding to the word lines thus switched, respectively.Type: GrantFiled: July 26, 1994Date of Patent: December 5, 1995Assignee: Hitachi, Ltd.Inventors: Hiroshi Sato, Keiichi Yoshida, Tetsuya Tsujikawa