Patents by Inventor Kazumasa Yanagisawa

Kazumasa Yanagisawa 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).

  • Publication number: 20040027860
    Abstract: A semiconductor integrated circuit includes non-volatile memory elements (PM1, PM2), each of which has a first source electrode, a first drain electrode, a floating gate electrode and a control gate electrode and is capable of having different threshold voltages, and read transistor elements (DM1, DM2), each of which has a second source electrode and a second drain electrode and is capable of having different mutual conductances according to the threshold voltage of the non-volatile memory element. The read transistor element has a switching state according to the electron injection state or the electron emission state, in other words, the writing state or the erasing state of the floating gate electrode. In a read operation, it is not necessary to cause a channel current to flow according to the threshold voltage of the non-volatile memory element.
    Type: Application
    Filed: July 28, 2003
    Publication date: February 12, 2004
    Inventors: Shoji Shukuri, Kazumasa Yanagisawa
  • Publication number: 20040016977
    Abstract: A body bias control system allows for independent design of a functional module, thereby reducing the burden of designing the module. The body bias control system provides a switch circuit having an area in which the body bias is controlled independently of its outside portion, for controlling the supply of body bias in the vicinity of the area. Preferably three types of switches are provided for switching the body bias to suitable levels for a standby mode, a mode of normal operation and a mode of high-speed operation.
    Type: Application
    Filed: May 6, 2003
    Publication date: January 29, 2004
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Masayuki Miyazaki, Yusuke Kanno, Goichi Ono, Toshinobu Shinbo, Yoshihiko Yasu, Kazumasa Yanagisawa, Takashi Kuraishi
  • Publication number: 20040004879
    Abstract: To reduce cost of defect redundancy and trimming in a semiconductor integrated circuit having multiple layer wirings and copper wirings, an address for salvaging a defect of a memory cell array in a semiconductor is stored by using a nonvolatile memory element constituting a floating electrode by a first layer of polysilicon, or the nonvolatile memory element is programmed in testing the semiconductor integrated circuit. As a result, a special process is not needed in forming the nonvolatile memory element. In other words, the nonvolatile memory element can be formed in a process of forming a CMOS device and an apparatus of a laser beam for programming is not needed since the programming is carried out in testing. Thus, the time necessary for programming can be shortened, and, therefore, testing costs can be reduced.
    Type: Application
    Filed: June 25, 2003
    Publication date: January 8, 2004
    Inventors: Koichiro Ishibashi, Shoji Shukuri, Kazumasa Yanagisawa, Junichi Nishimoto, Masanao Yamaoka, Masakazu Aoki
  • Publication number: 20030227041
    Abstract: A high integration dynamic random access memory is provided by this invention. Furthermore, a write method is provided such that the cell size of two-and three-transistor gain cell memories is reduced. A dynamic memory incorporating a thin-channel transistor as the write element such that long data storage retention is achieved in the memory devices of this invention. A dynamic memory cell having low operating power and high density is also realized by this invention.
    Type: Application
    Filed: June 11, 2002
    Publication date: December 11, 2003
    Inventors: Bryan Atwood, Kazuo Yano, Tomoyuki Ishii, Taro Osabe, Kazumasa Yanagisawa, Takeshi Sakata
  • Publication number: 20030222283
    Abstract: There are provided a plurality of bridge circuits which convert the test data information from a common test bus connected to a plurality of memories of different access data widths and address decode logics to the inherent access data widths of each memory and also convert the test address information from the common test bus to the inherent bit format of each memory to supply the result to the corresponding memory. The test address information is supplied in parallel from the common test bus to a plurality of memories to realize the parallel tests. Accordingly, the test data information can be supplied in parallel to a plurality of memories of different data widths and the address scan direction in the respective memories for the test address information can be uniformed to the particular direction depending on the inherent bit format. Thereby, the memory test efficiency by the match pattern for a plurality of on-chip memories can be improved.
    Type: Application
    Filed: May 7, 2003
    Publication date: December 4, 2003
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Yoshio Takazawa, Toshio Yamada, Kazumasa Yanagisawa, Takashi Hayasaka
  • Patent number: 6643182
    Abstract: A dynamic RAM includes sense amplifiers each formed of a latch circuit consisting of MOSFETs of a first and second conductivity types with the application of a first and second voltages to the sources thereof, respectively, and having a pair of input/output nodes corresponding to a first bit line pair which is connected with a number of dynamic memory cells, and further includes pairs of switching MOSFETs of the first conductivity type which connect selectively an input/output node pair of the latch circuits to a pair of second bit lines provided commonly to a plurality of the first bit line pair in response to the reception of the select signal. The switching MOSFETs have their threshold voltage set smaller in terms of absolute value than the threshold voltage of the MOSFETs of the first conductivity type of the latch circuits, and the select signal has its level of turning off the switching MOSFETs set greater in terms of absolute value than the first voltage with respect to the second voltage.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: November 4, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kazumasa Yanagisawa, Toshio Sasaki, Satoru Nakanishi, Yoshihiko Yasu
  • Patent number: 6628549
    Abstract: A semiconductor integrated circuit includes non-volatile memory elements (PM1, PM2), each of which has a first source electrode, a first drain electrode, a floating gate electrode and a control gate electrode and is capable of having different threshold voltages, and read transistor elements (DM1, DM2), each of which has a second source electrode and a second drain electrode and is capable of having different mutual conductances according to the threshold voltage of the non-volatile memory element. The read transistor element has a switching state according to the electron injection state or the electron emission state, in other words, the writing state or the erasing state of the floating gate electrode. In a read operation, it is not necessary to cause a channel current to flow according to the threshold voltage of the non-volatile memory element.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: September 30, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Shoji Shukuri, Kazumasa Yanagisawa
  • Patent number: 6611458
    Abstract: To reduce cost of defect redundancy and trimming in a semiconductor integrated circuit having multiple layer wirings and copper wirings, address for salvaging defect of a memory cell array in a semiconductor is stored by using a nonvolatile memory element constituting a floating electrode by a first layer of polysilicon, or the nonvolatile memory element is programmed in testing the semiconductor integrated circuit, thereby, a special process is not needed in forming the nonvolatile memory element, that is, the nonvolatile memory element can be formed in a process of forming CMOS device and apparatus of laser beam for programming is not needed since the programming is carried out in testing, time necessary for programming can be shortened and therefore, testing cost can be reduced.
    Type: Grant
    Filed: February 12, 2001
    Date of Patent: August 26, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Koichiro Ishibashi, Shoji Shukuri, Kazumasa Yanagisawa, Junichi Nishimoto, Masanao Yamaoka, Masakazu Aoki
  • Patent number: 6609236
    Abstract: A semiconductor IC device is designed using a memory core with a plurality of I/O lines, a transfer circuit module and a logic library which are produced beforehand and stored in a data base. The memory core and a logic circuit are arranged so that their I/O lines extend in the same direction. A transfer circuit including plural stages of switch groups is arranged between the I/O lines of the memory core and the I/O lines of the logic circuit. Switches forming each stage of switch group are formed between the I/O lines of the memory core and the I/O lines of the logic circuit. When one stage of or a small number of stages of switch groups are turned on, the I/O lines of the memory core and the I/O lines of the logic circuit are turned on, thereby forming a desired transfer pattern. The memory core is constructed by the combination of functional modules such as an amplifier module, a bank module and a power supply module.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: August 19, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Takao Watanabe, Kazushige Ayukawa, Ryo Fujita, Kazumasa Yanagisawa, Hitoshi Tanaka
  • Publication number: 20030141926
    Abstract: A semiconductor integrated circuit device provided with a first circuit block BLK1, a second circuit block DRV1 and a conversion circuit MIO1 for connecting the first circuit block to the second circuit block. The first circuit block includes a first mode for applying a supply voltage and a second mode for shutting off the supply voltage. The conversion circuit is provided with a function for maintaining the potential of an input node of the second circuit block at an operation potential, thereby suppressing a penetrating current flow when the first circuit block is in the second mode. The conversion circuit (MIO1 to MIO4) are commonly used for connecting circuit blocks.
    Type: Application
    Filed: January 27, 2003
    Publication date: July 31, 2003
    Inventors: Hiroyuki Mizuno, Yusuke Kanno, Kazumasa Yanagisawa, Yoshihiko Yasu, Nobuhiro Oodaira
  • Publication number: 20030145177
    Abstract: The present invention is directed to facilitate change in the specifications of an interface of a memory IP and to improve reusability of the memory IP. A memory module to be mounted on a system LSI or the like is constructed by a basic array and an interface. The basic array is constructed by direct peripheral circuits and a storage circuit. Library data of the basic array is stored in a storage medium such as a CD-R or a magnetic tape and distributed to the user. The library data includes layout pattern data, a logic simulation model defining the operation of the basic array, LSI pattern information such as a layout, device information such as characteristics of a MOS device and layout rules, interface information such as various signal timings, and device specification data such as terminal information.
    Type: Application
    Filed: December 30, 2002
    Publication date: July 31, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Kei Kato, Masanao Yamaoka, Keiichi Higeta, Kazumasa Yanagisawa, Shigeru Shimada, Kodo Yamauchi, Yoshihiro Shinozaki, Yasuo Taguchi
  • Publication number: 20030112652
    Abstract: On the first digital circuit, the circuits which must be operated even under the waiting condition such as an SRAM which is required to hold control data or the like even during the waiting condition of a semiconductor integrated circuit and a timer circuit for recovery from the waiting condition and for the waiting operation are formed. A gate insulation film of the MOS transistor forming the first digital circuit is formed to be thicker than that of the MOS transistor of the second digital circuit in which the circuits which are not operated during the waiting condition are formed. Accordingly, the sub-threshold leak current of the first digital circuit to be operated even during the waiting condition and the tunnel leak current of the gate electrode can be reduced. Moreover, when the semiconductor integrated circuit of the present invention is applied to a battery power supply system, the operation life of a battery can be extended.
    Type: Application
    Filed: November 7, 2002
    Publication date: June 19, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Shigeru Shimada, Kazumasa Yanagisawa
  • Publication number: 20030042965
    Abstract: A semiconductor device includes a differential level converter circuit that receives a first signal and outputs a second signal of greater amplitude. The differential level converter has a first MISFET pair for receiving the first signal, a second MISFET pair for enhancing the withstand voltage of the first MISFET pair, and a third MISFET pair with cross-coupled gates for latching the second signal from output. The film thickness of the gate insulating films of the second and third MISFET pairs is made thicker than that of the first MISFET pair, and the threshold voltages of the first and second MISFET pairs are made smaller than that of the third MISFET pair. This level converter circuit operates at high speed even if there is a large difference in the signal amplitude before and after level conversion.
    Type: Application
    Filed: August 5, 2002
    Publication date: March 6, 2003
    Inventors: Yusuke Kanno, Hiroyuki Mizuno, Kazumasa Yanagisawa
  • Publication number: 20030031066
    Abstract: A dynamic RAM includes sense amplifiers each formed of a latch circuit consisting of MOSFETs of a first and second conductivity types with the application of a first and second voltages to the sources thereof, respectively, and having a pair of input/output nodes corresponding to a first bit line pair which is connected with a number of dynamic memory cells, and further includes pairs of switching MOSFETs of the first conductivity type which connect selectively an input/output node pair of the latch circuits to a pair of second bit lines provided commonly to a plurality of the first bit line pair in response to the reception of the select signal. The switching MOSFETs have their threshold voltage set smaller in terms of absolute value than the threshold voltage of the MOSFETs of the first conductivity type of the latch circuits, and the select signal has its level of turning off the switching MOSFETs set greater in terms of absolute value than the first voltage with respect to the second voltage.
    Type: Application
    Filed: September 18, 2002
    Publication date: February 13, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Kazumasa Yanagisawa, Toshio Sasaki, Satoru Nakanishi, Yoshihiko Yasu
  • Publication number: 20020191445
    Abstract: A semiconductor integrated circuit includes non-volatile memory elements (PM 1, PM2), each of which has a first source electrode, a first drain electrode, a floating gate electrode and a control gate electrode and is capable of having different threshold voltages, and read transistor elements (DM1, DM2), each of which has a second source electrode and a second drain electrode and is capable of having different mutual conductances according to the threshold voltage of the non-volatile memory element. The read transistor element has a switching state according to the electron injection state or the electron emission state, in other words, the writing state or the erasing state of the floating gate electrode. In a read operation, it is not necessary to cause a channel current to flow according to the threshold voltage of the non-volatile memory element.
    Type: Application
    Filed: August 29, 2002
    Publication date: December 19, 2002
    Inventors: Shoji Shukuri, Kazumasa Yanagisawa
  • Patent number: 6480425
    Abstract: A dynamic RAM includes sense amplifiers each formed of a latch circuit consisting of MOSFETs of a first and second conductivity types with the application of a first and second voltages to the sources thereof, respectively, and having a pair of input/output nodes corresponding to a first bit line pair which is connected with a number of dynamic memory cells, and further includes pairs of switching MOSFETs of the first conductivity type which connect selectively an input/output node pair of the latch circuits to a pair of second bit lines provided commonly to a plurality of the first bit line pair in response to the reception of the select signal. The switching MOSFETs have their threshold voltage set smaller in terms of absolute value than the threshold voltage of the MOSFETs of the first conductivity type of the latch circuits, and the select signal has its level of turning off the switching MOSFETs set greater in terms of absolute value than the first voltage with respect to the second voltage.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: November 12, 2002
    Assignees: Hitachi, Ltd., Hitachi Ulsi Systems Co., Ltd.
    Inventors: Kazumasa Yanagisawa, Toshio Sasaki, Satoru Nakanishi, Yoshihiko Yasu
  • Patent number: 6466482
    Abstract: A semiconductor integrated circuit includes non-volatile memory elements (PM1, PM2), each of which has a first source electrode, a first drain electrode, a floating gate electrode and a control gate electrode and is capable of having different threshold voltages, and read transistor elements (DM1, DM2), each of which has a second source electrode and a second drain electrode and is capable of having different mutual conductances according to the threshold voltage of the non-volatile memory element. The read transistor element has a switching state according to the electron injection state or the electron emission state, in other words, the writing state or the erasing state of the floating gate electrode. In a read operation, it is not necessary to cause a channel current to flow according to the threshold voltage of the non-volatile memory element.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: October 15, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Shoji Shukuri, Kazumasa Yanagisawa
  • Patent number: 6463066
    Abstract: Provided is a high-throughput large-capacity ATM switch in which variation in memory access time and data output delay time generated in the case where a DRAM is used as a cell buffer of the ATM switch is absorbed. To realize this, the ATM switch comprises a first memory using a DRAM for storing cells, a second memory using an SRAM for switching and temporarily storing the cells before transferring the cells to the first memory, and a controller for generating write/read address and timing signals for the first and second memories. The controller generates read address and timing signals for the second memory and write address and timing signals for the first memory taking variation in access time or delay time based on access address of the first memory into account, so that the cells are output on destination output lines after the cells are switched and stored in the second memory and then stored in the first memory.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: October 8, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Norihiko Moriwaki, Kenichi Sakamoto, Akihiko Takase, Akio Makimoto, Kazumasa Yanagisawa
  • Publication number: 20020103961
    Abstract: To enhance the speed of first access (read access different in word line from the previous access) to a multi-bank memory, multi-bank memory macro structures are used. Data are held in a sense amplifier for every memory bank. When access is hit to the held data, data latched by the sense amplifier are output to thereby enhance the speed of first access to the memory macro structures. Namely, each memory bank is made to function as a sense amplifier cache. To enhance the hit ratio of such a sense amplifier cache more greatly, an access controller self-prefetches the next address (an address to which a predetermined offset has been added) after access to a memory macro structure so that data in the self-prefetched address are preread by a sense amplifier in another memory bank.
    Type: Application
    Filed: March 20, 2002
    Publication date: August 1, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Kazushige Ayukawa, Seiji Miura, Jun Satoh, Takao Watanabe, Kazumasa Yanagisawa, Yusuke Kanno, Hiroyuki Mizuno
  • Publication number: 20020064064
    Abstract: Outside-cell wiring that extends the upper part of a macro cell to the direction of X axis is composed of the wiring layer of the upper layer than a terminal for a signal of the macro cell and this terminal is formed to extend in the direction of Y axis (direction that intersects the direction of X axis) so that the outside-cell wiring can be secured for a plurality of wiring channels. The macro cell and the outside-cell wiring are connected via this signal terminal.
    Type: Application
    Filed: October 22, 2001
    Publication date: May 30, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Toshio Yamada, Kazumasa Yanagisawa, Yoshihiro Shinozaki, Hidetomo Aoyagi