Patents by Inventor Toshio Sunaga

Toshio Sunaga 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: 11829605
    Abstract: A memory device includes several normal memory circuits and a redundant memory circuit is disclosed. The several normal memory circuits include several normal memory arrays. The redundant memory circuit includes a redundant memory array. The several normal memory arrays share the redundant memory array. When a first normal memory cell of a first normal memory array of the several normal memory arrays is destructed, a first redundant memory cell of the redundant memory array replaces the first normal memory cell. When a second normal memory cell of a second normal memory array of the several normal memory arrays is destructed, a second redundant memory cell of the redundant memory array replaces the second normal memory cell.
    Type: Grant
    Filed: April 26, 2021
    Date of Patent: November 28, 2023
    Assignees: JIANGSU ADVANCED MEMORY TECHNOLOGY CO., LTD., SILOAM HOLDINGS CO., LTD.
    Inventors: Jui-Jen Wu, Toshio Sunaga, Tzu-Hao Yang
  • Patent number: 11621024
    Abstract: A calibration device which is configured for calibrating a memory is provided. The calibration device includes an input terminal, a first pull-up circuit, and a first comparator. The input terminal is coupled to an external resistor. The first pull-up circuit is coupled to the input terminal, and configured to receive a power supply voltage. The first pull-up circuit includes a plurality of first pull-up units. The first pull-up units are coupled to each other in parallel. The first comparator is coupled to the input terminal. The first comparator is configured to receive a proportion voltage which is corresponding to the power supply voltage, and output a first control signal to the first pull-up units, such that a resistance of each of the first pull-up units is equal to a resistance of the external resistor.
    Type: Grant
    Filed: April 26, 2021
    Date of Patent: April 4, 2023
    Assignees: JIANGSU ADVANCED MEMORY TECHNOLOGY CO., LTD., SILOAM HOLDINGS CO., LTD.
    Inventors: Jui-Jen Wu, Toshio Sunaga, Cho-Fan Chen
  • Publication number: 20220301611
    Abstract: A memory device includes a memory group and a control circuit. The memory group includes several memory banks. The control circuit is coupled to the memory group. The control circuit includes a tri-state logic enable circuit and an address decoding circuit. The tri-state logic enable circuit is configured to temporarily store several temporarily stored address signals, to output the several temporarily stored address signals according to a synchronization signal, to decode the several temporarily stored address signals to generate an enable signal, and to transmit the enable signal to one of the several memory banks. The address decoding circuit is configured to decode the several temporarily stored address signals to drive the one of the several memory banks.
    Type: Application
    Filed: April 26, 2021
    Publication date: September 22, 2022
    Inventors: Jui-Jen WU, Toshio SUNAGA, Hsiu-Chun TSAI
  • Publication number: 20220300167
    Abstract: A memory device includes several normal memory circuits and a redundant memory circuit is disclosed. The several normal memory circuits include several normal memory arrays. The redundant memory circuit includes a redundant memory array. The several normal memory arrays share the redundant memory array. When a first normal memory cell of a first normal memory array of the several normal memory arrays is destructed, a first redundant memory cell of the redundant memory array replaces the first normal memory cell. When a second normal memory cell of a second normal memory array of the several normal memory arrays is destructed, a second redundant memory cell of the redundant memory array replaces the second normal memory cell.
    Type: Application
    Filed: April 26, 2021
    Publication date: September 22, 2022
    Inventors: Jui-Jen WU, Toshio SUNAGA, Tzu-Hao YANG
  • Publication number: 20220293142
    Abstract: A calibration device which is configured for calibrating a memory is provided. The calibration device includes an input terminal, a first pull-up circuit, and a first comparator. The input terminal is coupled to an external resistor. The first pull-up circuit is coupled to the input terminal, and configured to receive a power supply voltage. The first pull-up circuit includes a plurality of first pull-up units. The first pull-up units are coupled to each other in parallel. The first comparator is coupled to the input terminal. The first comparator is configured to receive a proportion voltage which is corresponding to the power supply voltage, and output a first control signal to the first pull-up units, such that a resistance of each of the first pull-up units is equal to a resistance of the external resistor.
    Type: Application
    Filed: April 26, 2021
    Publication date: September 15, 2022
    Inventors: Jui-Jen WU, Toshio SUNAGA, Cho-Fan CHEN
  • Patent number: 11443789
    Abstract: A memory device includes a memory group and a control circuit. The memory group includes several memory banks. The control circuit is coupled to the memory group. The control circuit includes a tri-state logic enable circuit and an address decoding circuit. The tri-state logic enable circuit is configured to temporarily store several temporarily stored address signals, to output the several temporarily stored address signals according to a synchronization signal, to decode the several temporarily stored address signals to generate an enable signal, and to transmit the enable signal to one of the several memory banks. The address decoding circuit is configured to decode the several temporarily stored address signals to drive the one of the several memory banks.
    Type: Grant
    Filed: April 26, 2021
    Date of Patent: September 13, 2022
    Assignees: JIANGSU ADVANCED MEMORY TECHNOLOGY CO., LTD., SILOAM HOLDINGS CO., LTD.
    Inventors: Jui-Jen Wu, Toshio Sunaga, Hsiu-Chun Tsai
  • Patent number: 8605520
    Abstract: Systems and methods to improve reliability of sensing operations of semiconductor memory arrays requiring reading references such as MRAM or any type of phase change memory (PCM), and to improve yield of the memory arrays have been achieved. The memory array is divided into multiple parts, such as sections or segments. Reference word lines or reference bit lines or both are deployed in each of the multiple parts. Thus, the distance between an accessed line and the correspondent reference line is reduced, and hence the parasitic parameter tracking capability is enhanced significantly. Additionally spare reference word lines or spare reference bit lines can be deployed in each of the multiple parts.
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: December 10, 2013
    Assignee: MagIC Technologies, Inc.
    Inventors: Lejan Pu, Toshio Sunaga
  • Patent number: 8488357
    Abstract: Systems and methods for realizing reference currents to improve reliability of sensing operations of segmented semiconductor memory arrays have been achieved. Preferred embodiments of the invention comprise MRAM arrays but the invention could be applied to any other memories requiring access on small, segmented arrays. All embodiments of the invention comprise a folded bit lines scheme, either in adjacent bit lines or in segment-to-segment folded bit lines. In two embodiments alternate strapping of Poly-Si Word Lines in every second segment is achieved by metal layer of Read Word Line and Write Select Line. An embodiment has stored 1 and 0 cells on both sides of a selected segment to be read.
    Type: Grant
    Filed: October 22, 2010
    Date of Patent: July 16, 2013
    Assignee: MagIC Technologies, Inc.
    Inventors: Toshio Sunaga, Lejan Pu, Perng-Fei Yuh, Chao-Hung Chang
  • Publication number: 20120099358
    Abstract: Systems and methods for realizing reference currents to improve reliability of sensing operations of segmented semiconductor memory arrays have been achieved. Preferred embodiments of the invention comprise MRAM arrays but the invention could be applied to any other memories requiring access on small, segmented arrays. All embodiments of the invention comprise a folded bit lines scheme, either in adjacent bit lines or in segment-to-segment folded bit lines. In two embodiments alternate strapping of Poly-Si Word Lines in every second segment is achieved by metal layer of Read Word Line and Write Select Line. An embodiment has stored 1 and 0 cells on both sides of a selected segment to be read.
    Type: Application
    Filed: October 22, 2010
    Publication date: April 26, 2012
    Inventors: Toshio Sunaga, Lejan Pu, Perng-Fei Yuh, Chao-Hung Chang
  • Publication number: 20120069644
    Abstract: Systems and methods to improve reliability of sensing operations of semiconductor memory arrays requiring reading references such as MRAM or any type of phase change memory (PCM), and to improve yield of the memory arrays have been achieved. The memory array is divided into multiple parts, such as sections or segments. Reference word lines or reference bit lines or both are deployed in each of the multiple parts. Thus, the distance between an accessed line and the correspondent reference line is reduced, and hence the parasitic parameter tracking capability is enhanced significantly. Additionally spare reference word lines or spare reference bit lines can be deployed in each of the multiple parts.
    Type: Application
    Filed: September 22, 2010
    Publication date: March 22, 2012
    Inventors: Lejan Pu, Toshio Sunaga
  • Patent number: 7859935
    Abstract: A memory system includes: a high-voltage-supply booster circuit for driving an access control circuit from a low voltage for memory access to a high voltage for memory access by supplying electric charge that is stored in advance to an access control circuit in response to an access start request for a memory cell array; and a low-voltage-supply booster circuit for absorbing excess electric charge when the access control circuit is switched from the high voltage to the low voltage in response to an access end request for the memory cell array.
    Type: Grant
    Filed: December 25, 2006
    Date of Patent: December 28, 2010
    Assignee: International Business Machines Corporation
    Inventor: Toshio Sunaga
  • Patent number: 7843742
    Abstract: The present invention relates to a memory system including a memory cell array and being connected to an address input, a command input, and a data input/output, said memory system including latching circuits (RALTH and WALTH) for latching a read address and a write address being inputted from the address input, an address selection circuit (ACOMSEL) for selecting, as an access address, any one of the read address and the write address being latched in the latching circuits, a read latching circuit (PFLTH) for latching a read data being read from the memory cell array, a write latching circuit (DINLTH) for latching a write data being inputted from the data input/output and a control circuit (ACTL) for controlling the access address being selected by said address selection circuit in response to a command being inputted from said command input, said control circuit for controlling, if the memory cell corresponding to said selected access address is activated and further said selected access address is a write
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: November 30, 2010
    Assignee: International Business Machines Corporation
    Inventors: Toshio Sunaga, Norio Fujita
  • Publication number: 20100061156
    Abstract: The present invention relates to a memory system including a memory cell array and being connected to an address input, a command input, and a data input/output, said memory system including latching circuits (RALTH and WALTH) for latching a read address and a write address being inputted from the address input, an address selection circuit (ACOMSEL) for selecting, as an access address, any one of the read address and the write address being latched in the latching circuits, a read latching circuit (PFLTH) for latching a read data being read from the memory cell array, a write latching circuit (DINLTH) for latching a write data being inputted from the data input/output and a control circuit (ACTL) for controlling the access address being selected by said address selection circuit in response to a command being inputted from said command input, said control circuit for controlling, if the memory cell corresponding to said selected access address is activated and further said selected access address is a write
    Type: Application
    Filed: July 26, 2006
    Publication date: March 11, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Toshio Sunaga, Norio Fujita
  • Publication number: 20090231941
    Abstract: A memory system includes: a high-voltage-supply booster circuit for driving an access control circuit from a low voltage for memory access to a high voltage for memory access by supplying electric charge that is stored in advance to an access control circuit in response to an access start request for a memory cell array; and a low-voltage-supply booster circuit for absorbing excess electric charge when the access control circuit is switched from the high voltage to the low voltage in response to an access end request for the memory cell array.
    Type: Application
    Filed: December 25, 2006
    Publication date: September 17, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Toshio Sunaga
  • Patent number: 7522458
    Abstract: A memory including at least one memory cell array and an access control circuit for controlling access to the memory array. The access control circuit includes an access command circuit (ADRCTL) that receives a first (CE) and a second (ADV) input signals and outputs an access command signal (ACMDS) enabling commencement of memory access, and a command discriminating circuit (CMDDEC) that receives the first (CE) and second (ADV) input signals, a third (OE) and a fourth (WE) input signals, and a clock signal (CLK), and that outputs a command discriminating signal (WRITE) for specifying whether the access command signal is for a read operation or a write operation.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: April 21, 2009
    Assignee: International Business Machines Corporation
    Inventors: Toshio Sunaga, Hisatada Miyatake
  • Patent number: 7518942
    Abstract: The objective of the present invention is to provide a semiconductor storage device wherein a low active current is obtained by reducing the number of sense amplifiers to be activated at a time. An SDRAM has a divided word line structure, and includes a plurality of banks, each of which includes arrays AR1 to AR64 and 4K main word lines MWL. A row address signal is fetched in response to a row address strobe signal, and a segment address signal is fetched in response to a column address strobe signal. A main row decoder MRD activates main word lines MWL1, MWL5, MWL9 and MWL13 in response to the row address signal, and a segment row decoder SRD selects only an array AR1 in response to a segment address signal, and activates only 1K sense amplifiers SA corresponding to the selected array AR. When the main word lines MWL1, MWL5, MWL9 and MWL13 are activated, the segment word lines in arrays AR2 to AR64 are not activated, so that data are not destroyed.
    Type: Grant
    Filed: November 1, 2006
    Date of Patent: April 14, 2009
    Assignee: International Business Machines Corporation
    Inventor: Toshio Sunaga
  • Patent number: 7511981
    Abstract: A non-volatile memory device according to one embodiment comprises a plurality of memory cells each comprising a magneto resistive element and a selection transistor; wherein at least some of the memory cells are arranged into a two dimensional array; a first interconnect line extending in a first direction of the memory array and functioning as a gate electrode of a selection transistor included in each memory cell; a second interconnect line extending in the first direction of the memory array; a third interconnect line extending in a second direction; wherein the magneto resistive element of at least some of the memory cells is sandwiched between the second and third interconnect lines, wherein the second interconnect line extends at least partially along all magneto resistive elements in a particular one of the memory cells.
    Type: Grant
    Filed: October 22, 2007
    Date of Patent: March 31, 2009
    Assignee: International Business Machines Corporation
    Inventors: Hideo Asano, Koji Kitamura, Hisatada Miyatake, Kohki Noda, Toshio Sunaga, Hiroshi Umezaki
  • Patent number: 7489482
    Abstract: In the case of magnetic head of magnetoresistance effect type whose breakdown voltage is as low as 0.3 V, it is impractical to ignore even a very small amount of static electricity that occurs during fabrication or use. In one embodiment, the desired magnetic head is produced by forming an SiO2 layer on a silicon slider, thereby forming an SOI substrate; forming on the SOI substrate circuits to protect a TMR element from overvoltage and a read-write circuit; forming field effect transistors from an Si semiconductor layer (formed by reduction of the SiO2 layer or epitaxial growth on the SiO2 layer); forming three electrodes (source, gate, drain) on the Si semiconductor layer; forming a Schottky diode by Schottky contact (metal) with the Si semiconductor layer; forming overvoltage protective circuits of aluminum wiring on the SOI substrate; and forming a TMR element.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: February 10, 2009
    Assignee: Hitachi GLobal Storage Technologies Netherlands B.V.
    Inventors: Hiroyuki Ono, Hiroaki Suzuki, Toshio Sunaga, Hisatada Miyatake, Hideo Asano
  • Patent number: 7474557
    Abstract: A magnetic random access memory (MRAM) array is disclosed herein in which a plurality of wordlines and a plurality of bitlines are provided in matrix form, the wordlines including read wordlines and write wordlines, and memory elements are provided at the intersections of the wordlines and the bitlines, memory elements, respectively, including at least a ferromagnetic layer having a magnetization direction determined by the orientation of a magnetic field generated by an electric current passing through the bitline, and a read wordline driver connected to the memory array adapted to provide a first read signal to a first read wordline of a plurality of read wordlines, wherein a second read signal is provided to activate a second read wordline while the first read wordline remains activated.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: January 6, 2009
    Assignee: International Business Machines Corporation
    Inventors: Toshio Sunaga, Hisatada Miyatake, Koji Kitamura
  • Patent number: 7469243
    Abstract: Embodiments of the present invention provide method and device for searching fixed length data. The device includes a hash operation means for operating and outputting a hash value of inputted fixed length data, a data table memory consisting of N numbers of memory banks, where N is an integer that is more than and equal to 2, the data table memory for storing a data table holding a large number of fixed length data, a pointer table memory for storing a memory pointer table holding a memory address at which each fixed length datum is stored with the hash value as an index, and a comparison means for simultaneously comparing a plurality of fixed length data stored at the same memory address in the N numbers of memory banks with a single fixed length datum inputted to the hash operation means, the comparison means for outputting results of the comparison.
    Type: Grant
    Filed: January 27, 2004
    Date of Patent: December 23, 2008
    Assignee: International Business Machines Corporation
    Inventors: Masaya Mori, Shinpei Watanabe, Yoshihisa Takatsu, Toshio Sunaga