Patents by Inventor Masaaki Terasawa

Masaaki Terasawa 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: 7965563
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Grant
    Filed: February 2, 2009
    Date of Patent: June 21, 2011
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Patent number: 7652924
    Abstract: The present invention is directed to largely reduce peak current at the time of operation of a boosting circuit provided for an EEPROM. In the erase/write operation, first, a low-frequency clock signal as a selection clock signal is input by a low-frequency clock control signal to a charge pump. After lapse of a certain period (about ? of fall time), a high-frequency clock signal having a frequency higher than that of the low-frequency clock signal is output by a high-frequency clock control signal and is input as the selection clock signal to the charge pump to boost a voltage to a predetermined voltage level. In such a manner, while suppressing the peak of consumption current, the fall time of the boosted voltage can be shortened.
    Type: Grant
    Filed: July 11, 2008
    Date of Patent: January 26, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Yoshiki Kawajiri, Masaaki Terasawa, Takanori Yamazoe
  • Publication number: 20090157953
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Application
    Filed: February 2, 2009
    Publication date: June 18, 2009
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Patent number: 7512007
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: March 31, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Masaaki Terasawa, Yoshiki Kawajiri, Takanori Yamazoe
  • Patent number: 7505329
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: March 17, 2009
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems, Co., Ltd.
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Publication number: 20080279011
    Abstract: The present invention is directed to largely reduce peak current at the time of operation of a boosting circuit provided for an EEPROM. In the erase/write operation, first, a low-frequency clock signal as a selection clock signal is input by a low-frequency clock control signal to a charge pump. After lapse of a certain period (about ? of fall time), a high-frequency clock signal having a frequency higher than that of the low-frequency clock signal is output by a high-frequency clock control signal and is input as the selection clock signal to the charge pump to boost a voltage to a predetermined voltage level. In such a manner, while suppressing the peak of consumption current, the fall time of the boosted voltage can be shortened.
    Type: Application
    Filed: July 11, 2008
    Publication date: November 13, 2008
    Inventors: YOSHIKI KAWAJIRI, Masaaki Terasawa, Takanori Yamazoe
  • Patent number: 7411831
    Abstract: The present invention is directed to largely reduce peak current at the time of operation of a boosting circuit provided for an EEPROM. In the erase/write operation, first, a low-frequency clock signal as a selection clock signal is input by a low-frequency clock control signal to a charge pump. After lapse of a certain period (about ? of fall time), a high-frequency clock signal having a frequency higher than that of the low-frequency clock signal is output by a high-frequency clock control signal and is input as the selection clock signal to the charge pump to boost a voltage to a predetermined voltage level. In such a manner, while suppressing the peak of consumption current, the fall time of the boosted voltage can be shortened.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: August 12, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Yoshiki Kawajiri, Masaaki Terasawa, Takanori Yamazoe
  • Publication number: 20080137429
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Application
    Filed: January 9, 2008
    Publication date: June 12, 2008
    Inventors: Masaaki TERASAWA, Yoshiki Kawajiri, Takanori Yamazoe
  • Patent number: 7385853
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: June 10, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Masaaki Terasawa, Yoshiki Kawajiri, Takanori Yamazoe
  • Publication number: 20080028134
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Application
    Filed: September 25, 2007
    Publication date: January 31, 2008
    Inventors: Kiyoshi MATSUBARA, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Publication number: 20070274129
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Application
    Filed: June 29, 2007
    Publication date: November 29, 2007
    Inventors: Masaaki Terasawa, Yoshiki Kawajiri, Takanori Yamazoe
  • Patent number: 7295476
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Grant
    Filed: January 25, 2007
    Date of Patent: November 13, 2007
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Publication number: 20070247920
    Abstract: The present invention is directed to largely reduce peak current at the time of operation of a boosting circuit provided for an EEPROM. In the erase/write operation, first, a low-frequency clock signal as a selection clock signal is input by a low-frequency clock control signal to a charge pump. After lapse of a certain period (about ? of fall time), a high-frequency clock signal having a frequency higher than that of the low-frequency clock signal is output by a high-frequency clock control signal and is input as the selection clock signal to the charge pump to boost a voltage to a predetermined voltage level. In such a manner, while suppressing the peak of consumption current, the fall time of the boosted voltage can be shortened.
    Type: Application
    Filed: June 26, 2007
    Publication date: October 25, 2007
    Inventors: Yoshiki Kawajiri, Masaaki Terasawa, Takanori Yamazoe
  • Patent number: 7254084
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Grant
    Filed: May 27, 2005
    Date of Patent: August 7, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Masaaki Terasawa, Yoshiki Kawajiri, Takanori Yamazoe
  • Patent number: 7251162
    Abstract: The present invention is directed to largely reduce peak current at the time of operation of a boosting circuit provided for an EEPROM. In the erase/write operation, first, a low-frequency clock signal as a selection clock signal is input by a low-frequency clock control signal to a charge pump. After lapse of a certain period (about ? of fall time), a high-frequency clock signal having a frequency higher than that of the low-frequency clock signal is output by a high-frequency clock control signal and is input as the selection clock signal to the charge pump to boost a voltage to a predetermined voltage level. In such a manner, while suppressing the peak of consumption current, the fall time of the boosted voltage can be shortened.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: July 31, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Yoshiki Kawajiri, Masaaki Terasawa, Takanori Yamazoe
  • Publication number: 20070133308
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Application
    Filed: January 25, 2007
    Publication date: June 14, 2007
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Patent number: 7184321
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: February 27, 2007
    Assignees: Hitachi Ulsi Systems Co., Ltd., Renesas Technology Corp.
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Publication number: 20060114737
    Abstract: A delay from the release of a low power consumption mode of nonvolatile memory to the restart of read operation is reduced. Nonvolatile memory which can electrically rewrite stored information has in well regions plural nonvolatile memory cell transistors having drain electrodes and source electrodes respectively coupled to bit lines and source lines and gate electrodes coupled to word lines and storing information based on a difference between threshold voltages to a word line select level in read operation, and the nonvolatile memory has a low power consumption mode. In the low power consumption mode, a second voltage lower than a circuit ground voltage and higher than a first negative voltage necessary for read operation is supplied to the well regions and word lines. When boost forming a rewriting negative voltage therein, a circuit node at a negative voltage is not the circuit ground voltage in the low power consumption mode.
    Type: Application
    Filed: May 27, 2005
    Publication date: June 1, 2006
    Inventors: Masaaki Terasawa, Yoshiki Kawajiri, Takanori Yamazoe
  • Publication number: 20060034129
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Application
    Filed: October 7, 2005
    Publication date: February 16, 2006
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba
  • Patent number: 6999350
    Abstract: A semiconductor device having an electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: February 14, 2006
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kiyoshi Matsubara, Naoki Yashiki, Shiro Baba, Takashi Ito, Hirofumi Mukai, Masanao Sato, Masaaki Terasawa, Kenichi Kuroda, Kazuyoshi Shiba