Patents by Inventor Katsutaka Kimura

Katsutaka Kimura 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).

  • Patent number: 6330178
    Abstract: Since a ferroelectric memory device cannot employ a VCC/2 precharge scheme widely used in DRAM, its array noise and power consumption are large. Further, a ferroelectric capacitor is deteriorated in its characteristics due to its fatigue and imprint. To avoid this, data line pairs are precharged to two voltages VCC and VSS. As a result, a voltage on a data line in a memory cell array MCA varies symmetrically with respect to VCC/2 as its center to thereby reduce the array noise. Further, when early sense and early precharge operations are carried out based on charge sharing between data lines of different precharge voltages, the power consumption can be reduced. Furthermore, when the precharge voltages are switched for respective data lines, reverse and non-reverse polarization are alternately carried out in the ferroelectric capacitor in the memory cell to suppress its fatigue and imprint.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: December 11, 2001
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems, Co., Ltd.
    Inventors: Takeshi Sakata, Tomonori Sekiguchi, Hiroki Fujisawa, Katsutaka Kimura, Masanori Isoda, Kazuhiko Kajigaya
  • Publication number: 20010046153
    Abstract: In a large scale integrated DRAM in pursuit of micro fabrication, data line-word line coupling capacitances are unbalanced between paired data lines. An imbalance in data line-word line means generation of large noise when the data lines are subjected to amplification, which is highly likely invite deterioration of very small signals on the data lines and erroneous amplification of data.
    Type: Application
    Filed: August 8, 2001
    Publication date: November 29, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Tomonori Sekiguchi, Riichiro Takemura, Kazuhiko Kajigaya, Katsutaka Kimura, Tsugio Takahashi
  • Publication number: 20010040822
    Abstract: Each memory cell of a nonvolatile semiconductor memory, essentially, consists of a one-transistor type memory cell such as a MOSFET having a floating gate electrode. When an electric programming operation is carried out, a positive voltage is applied to an n type drain region, a negative voltage is applied to a control gate and a source region is grounded. When an erasing operation is carried out, the positive voltage is applied to the control gate while all the other electrodes and a semiconductor substrate are grounded. Low power consumption can be accomplished because both of the programming operation and erasing operations are carried out by utilizing a tunneling mechanism. Furthermore, because the negative voltage applied to the word line, a drain voltage at the time of programming of data can be lowered, so that degradation of a gate oxide film at a channel portion can be mitigated.
    Type: Application
    Filed: June 15, 2001
    Publication date: November 15, 2001
    Inventors: Masataka Kato, Tetsuo Adachi, Toshihiro Tanaka, Toshio Sasaki, Hitoshi Kume, Katsutaka Kimura
  • Publication number: 20010036106
    Abstract: Each memory cell of a nonvolatile semiconductor memory, essentially, consists of a one-transistor type memory cell such as a MOSFET having a floating gate electrode. When an electric programming operation is carried out, a positive voltage is applied to an n type drain region, a negative voltage is applied to a control gate and a source region is grounded. When an erasing operation is carried out, the positive voltage is applied to the control gate while all the other electrodes and a semiconductor substrate are grounded. Low power consumption can be accomplished because both of the programming operation and erasing operations are carried out by utilizing a tunneling mechanism. Furthermore, because the negative voltage applied to the word line, a drain voltage at the time of programming of data can be lowered, so that degradation of a gate oxide film at a channel portion can be mitigated.
    Type: Application
    Filed: June 15, 2001
    Publication date: November 1, 2001
    Inventors: Masataka Kato, Tetsuo Adachi, Toshihiro Tanaka, Toshio Sasaki, Hitoshi Kume, Katsutaka Kimura
  • Publication number: 20010037431
    Abstract: In a digital information system for realizing the sale of information or the like having a commercial value in the form of a digital signal, and an audio processor, and signal processor suitably used with the system, when a digital signal is received/delivered, a digital signal source is connected directly to a player for receiving and storing a specified information, which is reproduced by the player independently. A voice interval of a digital audio signal is processed to realize the slow and fast playback. The system includes a data compressor and a data extender of simple configuration. The value of the digital signal received/delivered can be exhibited directly. A selling system is constructed easily, and the player is simple in configuration and easy to operate by anyone.
    Type: Application
    Filed: June 22, 2001
    Publication date: November 1, 2001
    Inventors: Nobuo Hamamoto, Minoru Nagata, Masatoshi Ohtake, Katsutaka Kimura, Toshio Sasaki, Hiroshi Kishida, Isamu Orita, Katsuro Sasaki, Naoki Ozawa, Kazuhiro Kondo, Toshiaki Masuhara, Tadashi Onishi, Hidehito Obayashi, Kiyoshi Aiki, Hisashi Horikoshi
  • Patent number: 6285597
    Abstract: A control of a flash memory includes control for supplying a pulse-shaped voltage to each of non-volatile memory cells until a threshold voltage of the non-volatile memory cell having a first threshold voltage is changed to a second threshold voltage. The control involves a first write mode (coarse write) in which the amount of change in threshold voltage of each non-volatile memory cell, which is varied each time the pulse-shaped voltage is applied, is relatively rendered high, and a second write mode (high-accuracy write) in which the amount of change in threshold voltage thereof is relatively rendered low. As compared with the high-accuracy mode, the number of pulses required to change the threshold voltage of each memory cell is smaller than that in the coarse write mode. Therefore, the number of verify operations at the time that the coarse write mode is used, is small and hence the entire write operation can be speeded up.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: September 4, 2001
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Takayuki Kawahara, Hiroshi Sato, Atsushi Nozoe, Keiichi Yoshida, Satoshi Noda, Shoji Kubono, Hiroaki Kotani, Katsutaka Kimura
  • Publication number: 20010017558
    Abstract: A clock recovery circuit is provided for use in a memory with a clock synchronized interface, wherein an external clock is temporarily intercepted to shorten lock-in time when an internal clock is to be generated from the external clock. The clock recovery circuit includes a delay circuit array, receiving the external clock, for generating reference clocks, a control circuit comparing phases of the external clock and of the reference clocks and detecting the number of delay stages required for locking in, and a latching circuit for holding the number of delay stages required for locking in. Once synchronism is detected, the generation of internal clock can be resumed in a short period of time even if the supply of the external clock is temporarily suspended.
    Type: Application
    Filed: April 24, 2001
    Publication date: August 30, 2001
    Inventors: Satoru Hanzawa, Takeshi Sakata, Katsutaka Kimura
  • Patent number: 6281725
    Abstract: A clock recovery circuit is provided for use in a memory with a clock synchronized interface or the like, wherein an external clock is temporarily intercepted to shorten the lock-in time when an internal clock is to be generated from the external clock. The clock recovery circuit includes a delay circuit array, into which an external clock is inputted, for generating a plurality of reference clocks, a control circuit for comparing the phases of the external clock and of the plurality of reference clocks and detecting the number of delay stages of the delay circuits required for locking in, and latching circuit for holding the number of delay stages required for locking in. Once synchronism is detected and the number of delay stages required for locking in are held in the latching circuit, the generation of the internal clock can be resumed in a short period of time even if the supply of the external clock is temporarily suspended.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: August 28, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Hanzawa, Takeshi Sakata, Katsutaka Kimura
  • Patent number: 6282611
    Abstract: In a digital information system for realizing the sale of information or the like having a commercial value in the form of a digital signal, and an audio processor, and signal processor suitably used with the system, when a digital signal is received/delivered, a digital signal source is connected directly to a player for receiving and storing a specified information, which is reproduced by the player independently. A voice interval of a digital audio signal is processed to realize the slow and fast playback. The system includes a data compressor and a data extender of simple configuration. The value of the digital signal received/delivered can be exhibited directly. A selling system is constructed easily, and the player is simple in configuration and easy to operate by anyone.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: August 28, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Hamamoto, Minoru Nagata, Masatoshi Ohtake, Katsutaka Kimura, Toshio Sasaki, Hiroshi Kishida, Isamu Orita, Katsuro Sasaki, Naoki Ozawa, Kazuhiro Kondo, Toshiaki Masuhara, Tadashi Onishi, Hidehito Obayashi, Kiyoshi Aiki, Hisashi Horikoshi
  • Patent number: 6278628
    Abstract: In a large scale integrated DRAM in pursuit of micro fabrication, data line-word line coupling capacitances are unbalanced between paired data lines. A data line-word line imbalance generates large noise when the data lines are subjected to amplification, which is highly likely to invite deterioration of very small signals on the data lines and erroneous amplification of data. One or a few of a plurality of word lines connected to a plurality of memory cells connected to one data line are alternately connected to subword driver arrays arranged on the opposing sides of a memory array. Positive and negative word line noise components cancel each other in the subword drivers when the data lines are subjected to amplification, so that the word line noise can be reduced. Therefore, signals read out by sense amplifiers can be prevented from deterioration thereby to increase the reliability of memory operation.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: August 21, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tomonori Sekiguchi, Riichiro Takemura, Kazuhiko Kajigaya, Katsutaka Kimura, Tsugio Takahashi
  • Patent number: 6272042
    Abstract: Each memory cell of a nonvolatile semiconductor memory, essentially, consists of a one-transistor type memory cell such as a MOSFET having a floating gate electrode. When an electric programming operation is carried out, a positive voltage is applied to an n type drain region, a negative voltage is applied to a control gate and a source region is grounded. When an erasing operation is carried out, the positive voltage is applied to the control gate while all the other electrodes and a semiconductor substrate are grounded. Low power consumption can be accomplished because both of the programming operation and erasing operations are carried out by utilizing a tunneling mechanism. Furthermore, because the negative voltage applied to the word line, a drain voltage at the time of programming of data can be lowered, so that degradation of a gate oxide film at a channel portion can be mitigated.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: August 7, 2001
    Assignee: Hitachi, LTD
    Inventors: Masataka Kato, Tetsuo Adachi, Toshihiro Tanaka, Toshio Sasaki, Hitoshi Kume, Katsutaka Kimura
  • Publication number: 20010002702
    Abstract: When a phase shift method is used as lithography where sense amplifiers are alternately placed in a one intersecting-point memory capable of implementing a reduction in the area of a DRAM, it was difficult to layout data lines in a boundary region between sense amplifiers and each memory array. Therefore, there is provided a semiconductor device according to the present invention. In the semiconductor device, two data lines continuous within the sub memory arrays or interposed therebetween are connected to the adjacent sense amplifiers as a system for drawing data lines from sub memory arrays (SMA) to sense amplifiers (SA) when the sense amplifiers are alternately placed. Namely, the number of data lines interposed between data lines respectively connected to two adjacent sense amplifiers is set to even numbers (0, 2, 4, . . . ).
    Type: Application
    Filed: November 29, 2000
    Publication date: June 7, 2001
    Inventors: Riichiro Takemura, Tomonori Sekiguchi, Katsutaka Kimura, Kazuhiko Kajigaya, Tsugio Takahashi
  • Patent number: 6243290
    Abstract: The present invention provides a nonvolatile semiconductor memory device for multilevel data storage that simultaneously carries out programming of multilevel data and subsequent verification at a high programming throughput.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: June 5, 2001
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hideaki Kurata, Naoki Kobayashi, Takashi Kobayashi, Katsutaka Kimura, Hitoshi Kume, Shunichi Saeki
  • Patent number: 6205556
    Abstract: Herein disclosed is a data processing system having a memory packaged therein for realizing a large-scale and high-speed parallel distributed processing and, especially, a data processing system for the neural network processing. The neural network processing system according to the present invention comprises: a memory circuit for storing neuron output values, connection weights, the desired values of outputs, and data necessary for learning; an input/output circuit for writing or reading data in or out of said memory circuit; a processing circuit for performing a processing for determining the neuron outputs such as the product, sum and nonlinear conversion of the data stored in said memory circuit, a comparison of the output value and its desired value, and a processing necessary for learning; and a control circuit for controlling the operations of said memory circuit, said input/output circuit and said processing circuit.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: March 20, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Takao Watanabe, Katsutaka Kimura, Kiyoo Itoh, Yoshiki Kawajiri
  • Publication number: 20010000023
    Abstract: A control of a flash memory includes control for supplying a pulse-shaped voltage to each of non-volatile memory cells until a threshold voltage of the non-volatile memory cell having a first threshold voltage is changed to a second threshold voltage. The control involves a first write mode (coarse write) in which the amount of change in threshold voltage of each non-volatile memory cell, which is varied each time the pulse-shaped voltage is applied, is relatively rendered high, and a second write mode (high-accuracy write) in which the amount of change in threshold voltage thereof is relatively rendered low. As compared with the high-accuracy mode, the number of pulses required to change the threshold voltage of each memory cell is smaller than that in the coarse write mode. Therefore, the number of verify operations at the time that the coarse write mode is used, is small and hence the entire write operation can be speeded up.
    Type: Application
    Filed: November 29, 2000
    Publication date: March 15, 2001
    Inventors: Takayuki Kawahara, Hiroshi Sato, Atsushi Nozoe, Keiichi Yoshida, Satoshi Noda, Shoji Kubono, Hiroaki Kotani, Katsutaka Kimura
  • Patent number: 6201735
    Abstract: Each memory cell of a nonvolatile semiconductor memory, essentially, consists of a one-transistor type memory cell such as a MOSFET having a floating gate electrode. When an electric programming operation is carried out, a positive voltage is applied to an n type drain region, a negative voltage is applied to a control gate and a source region is grounded. When an erasing operation is carried out, the positive voltage is applied to the control gate while all the other electrodes and a semiconductor substrate are grounded. Low power consumption can be accomplished because both of the programming operation and erasing operations are carried out by utilizing a tunneling mechanism. Furthermore, because the negative voltage is applied to the word line, a drain voltage at the time of programming of data can be lowered, so that degradation of a gate oxide film at a channel portion can be mitigated.
    Type: Grant
    Filed: July 29, 1999
    Date of Patent: March 13, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Masataka Kato, Tetsuo Adachi, Toshihiro Tanaka, Toshio Sasaki, Hitoshi Kume, Katsutaka Kimura
  • Patent number: 6181603
    Abstract: To enable one non-volatile memory cell to store four-value information, three different kinds of threshold voltages are serially applied to a word line in a verify operation to execute a write operation, the threshold voltages of the memory cell are controlled, and two-value (one-bit) information corresponding to the four-value (two-bit) information to be written are synthesized by a write data conversion circuit for each of the write operations carried out three times. In this way, the four-value (two-bit) information are written into one memory cell, and the memory capacity of the memory cell can be increased. In the information read operation, three different kinds of voltages are applied to a word line, three kinds of two-value (one-bit) information so read out are synthesized by a read conversion circuit and the memory information of the memory cell are converted to the two-bit information.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: January 30, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Yusuke Jyouno, Takayuki Kawahara, Katsutaka Kimura
  • Patent number: 6163485
    Abstract: A control of a flash memory includes control for supplying a pulse-shaped voltage to each of non-volatile memory cells until a threshold voltage of the non-volatile memory cell having a first threshold voltage is changed to a second threshold voltage. The control involves a first write mode (coarse write) in which the amount of change in threshold voltage of each non-volatile memory cell, which is varied each time the pulse-shaped voltage is applied, is relatively rendered high, and a second write mode (high-accuracy write) in which the amount of change in threshold voltage thereof is relatively rendered low. As compared with the high-accuracy mode, the number of pulses required to change the threshold voltage of each memory cell is smaller than that in the coarse write mode. Therefore, the number of verify operations at the time that the coarse write mode is used, is small and hence the entire write operation can be speeded up.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: December 19, 2000
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Takayuki Kawahara, Hiroshi Sato, Atsushi Nozoe, Keiichi Yoshida, Satoshi Noda, Shoji Kubono, Hiroaki Kotani, Katsutaka Kimura
  • Patent number: 6134148
    Abstract: A control of a flash memory includes control for supplying a pulse-shaped voltage to each of non-volatile memory cells until a threshold voltage of the non-volatile memory cell having a first threshold voltage is changed to a second threshold voltage. The control involves a first write mode (coarse write) in which the amount of change in threshold voltage of each non-volatile memory cell, which is varied each time the pulse-shaped voltage is applied, is relatively rendered high, and a second write mode (high-accuracy write) in which the amount of change in threshold voltage thereof is relatively rendered low. As compared with the high-accuracy mode, the number of pulses required to change the threshold voltage of each memory cell is smaller than that in the coarse write mode. Therefore, the number of verify operations at the time that the coarse write mode is used, is small and hence the entire write operation can be speeded up.
    Type: Grant
    Filed: August 20, 1999
    Date of Patent: October 17, 2000
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Takayuki Kawahara, Hiroshi Sato, Atsushi Nozoe, Keiichi Yoshida, Satoshi Noda, Shoji Kubono, Hiroaki Kotani, Katsutaka Kimura
  • Patent number: 6101123
    Abstract: Each memory cell of a nonvolatile semiconductor memory essentially consisting of a one-transistor type memory cell such as a MOSFET having a floating gate electrode. When an electric programming operation is carried out, a positive voltage is applied to an n type drain region, a negative voltage is applied to a control gate and a source region is grounded. When an erasing operation is carried out, the positive voltage is applied to the control gate while all the other electrodes and a semiconductor substrate are grounded. Low power consumption can be accomplished because both of the programming operation and erasing operations are carried out by utilizing a tunneling mechanism. Particularly because the negative voltage is used for the word line, a drain voltage at the time of programming of data can be lowered, so that degradation of a gate oxide film at a channel portion can be mitigated.
    Type: Grant
    Filed: April 8, 1999
    Date of Patent: August 8, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Masataka Kato, Tetsuo Adachi, Toshihiro Tanaka, Toshio Sasaki, Hitoshi Kume, Katsutaka Kimura