Patents by Inventor Takashi Oshima

Takashi Oshima 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: 8180951
    Abstract: A memory system for transmitting data to and receiving data from a host apparatus includes a semiconductor memory and an access-controlling part. The semiconductor memory has storage areas identified by physical addresses, stores data in each of the storage areas, performs data write in accordance with a request made by the host apparatus. The access-controlling part selects a recommended address, which is recommended to be used in a next data write, on the basis of operation information about a factor that influences time consumed for data write in the semiconductor memory, and outputs the recommended address to the host apparatus.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: May 15, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Oshima
  • Patent number: 8169350
    Abstract: A wireless receiving circuit having an analog-digital converter of digital calibration type constituted by plural analog-digital converter units, shares portions about digital calibration, and applies the result of calibration of one analog-digital converter unit to other analog-digital converter units to appropriately perform each digital calibration of the plural analog-digital converter units. For example, in a wireless receiving circuit having an analog-digital converter of digital calibration type constituted of an analog-digital converter unit of I side and an analog-digital converter unit of Q side, portions about digital calibration are shared, and a calibration result of I side is applied to Q side.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: May 1, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Oshima, Taizo Yamawaki
  • Patent number: 8145831
    Abstract: A memory system, which is connected to a host device, includes a memory, a host interface which receives a command and an address, which are output from the host device, and a controller which operates in one of a first mode in which the controller converts the address which is received by the host interface and accesses the memory by using the converted address, and a second mode in which the host device directly accesses the memory by using the address which is received by the host interface, the controller controlling switching between the first mode and second mode in accordance with the command.
    Type: Grant
    Filed: August 6, 2010
    Date of Patent: March 27, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Oshima, Makoto Moriya
  • Patent number: 8131912
    Abstract: A memory system including a nonvolatile memory, a first controller connected to a host equipment, the first controller controlling the entire memory system, a second controller connected to the first controller and also connected to the nonvolatile memory, the second controller controlling an access process to said nonvolatile memory, the second controller receives a command via the first controller and carries out the access process to the nonvolatile memory according to the command, the command being input from the host equipment.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: March 6, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Isao Ozawa, Takashi Oshima
  • Publication number: 20120038498
    Abstract: To improve resolution of a built-in A/D converter by reducing the area occupied by a chip of the built-in A/D converter in a semiconductor integrated circuit that is mounted in an on-vehicle millimeter wave radar device and which incorporates an A/D converter and an MPU. In the semiconductor integrated circuit, a plurality of reception signals of the radar device is A/D-converted by a single digital correction type A/D converter. The digital correction type A/D converter of the single A/D converter is a foreground digital correction type A/D converter that sequentially A/D-converts the reception signals output from a multiplexer of a receiving interface. The single A/D converter includes a pipeline type A/D converter having a plurality of cascade-coupled converters. The semiconductor integrated circuit comprises a correction signal generating unit, a digital correction D/A converter, and a digital correction unit for digital correction.
    Type: Application
    Filed: August 1, 2011
    Publication date: February 16, 2012
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Takashi OSHIMA, Tatsuji MATSUURA, Naoki YADA, Takahiro MIKI, Akihiro KITAGAWA, Tetsuo MATSUI, Kunihiko USUI
  • Patent number: 8102289
    Abstract: In the digital calibration technique of the conventional time-interleaved analog/digital converter, it is impossible to perform highly-accurate calibration that supports a high-speed sampling rate of the next-generation application and achieves a high resolution. For its solution, a reference A/D conversion unit is connected in parallel to an input common to a time-interleaved A/D converter to be a calibration target, and the output of each unitary A/D conversion unit which makes up the time-interleaved A/D converter is calibrated in a digital region by using a low-speed high-resolution A/D conversion result output from the reference A/D conversion unit. Also, fCLK/N (fCLK represents an overall sampling rate of the time-interleaved A/D converter, and N is relatively prime to the number of unitary A/D conversion units connected in parallel M) is set as the operation clock frequency of the reference A/D conversion unit.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: January 24, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Oshima, Taizo Yamawaki, Tomomi Takahashi
  • Patent number: 8090416
    Abstract: Conventional digital calibration type analog-to-digital converters cannot converge calibration within an preamble period of a packet signal. An analog-to-digital converter is subjected to digital calibration using a beacon signal, a polling signal, or another user signal or a signal applied from a transceiver side to a receiver side. Some or all of circuits are brought into a sleep mode in a period except data reception and the analog-to-digital converter calibration such that a signal monitor unit detects another signal to activate the circuit in the sleep mode for performing the calibration of the analog-to-digital converter for reducing the power consumption.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: January 3, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Oshima, Taizo Yamawaki
  • Publication number: 20110267211
    Abstract: In this invention, the accuracy between an input analog voltage and a digital output signal can be enhanced. A background digital correction type A/D converter includes a reference A/D conversion unit, a main A/D conversion unit, and a digital corrector. The main A/D conversion unit executes an A/D converting operation at a high speed, whereas the reference A/D conversion unit executes an A/D converting operation with high resolution, respectively. Each of main digital output signals of the main A/D conversion unit and a reference digital output signal of the reference A/D conversion unit are supplied to one input terminal of the digital corrector and the other input terminal thereof respectively. The digital corrector outputs a correction-processing digital output signal. The reference A/D conversion unit includes a ?? A/D converter and a Nyquist filter. The Nyquist filter suppresses a high-frequency quantization error of the ?? analog-digital converter.
    Type: Application
    Filed: April 27, 2011
    Publication date: November 3, 2011
    Inventors: Takashi OSHIMA, Tomomi TAKAHASHI
  • Patent number: 8004445
    Abstract: In a wireless chip receiving the multi-rate data according to the related art, power consumption and a circuit area of an analog-to-digital converter become large. In a digital calibration type analog-to-digital converter including both a reference analog-to-digital conversion unit and a main analog-to-digital conversion unit, when processing the high-sample rate wireless receive signal, both the reference analog-to-digital conversion unit and the main analog-to-digital conversion unit are operated to configure a general digital calibration type analog-to-digital converter, and when processing a low-sample rate wireless receive signal, analog-to-digital conversion is performed by using the reference analog-to-digital conversion unit and operations of the main analog-to-digital conversion unit or the like are stopped to remarkably reduce power consumption.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: August 23, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Oshima, Taizo Yamawaki
  • Patent number: 7969781
    Abstract: A memory unit includes a plurality of first blocks each having a first block size. Each of the first blocks stores data of a plurality of second blocks each having a second block size which is smaller than the first block size. A control unit writes the data of the second block in the first block. The control unit is configured such that in a case where the second block to be written is a block that is to be written in the same first block as the second block that is already written in the first block, the second block to be written is written in the same first block even if an address of the second block to be written is not consecutive to an address of the second block that is already written in the first block.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: June 28, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Oshima
  • Patent number: 7957710
    Abstract: A DCDC converter includes a signal splitting unit that splits an input signal into N signal components; N DCDC converter elements that process individually the N split signals; and an adder that adds outputs from the plural DCDC converter elements to generate output signals. Each of the DCDC converter elements has an operation band narrower than an applicable frequency band of the input signal, and selects a design parameter that allows a conversion efficiency of the DCDC converter elements to be optimized for any band of the applicable frequency bands. For example, the parameter of a PMOS transistor and a NMOS transistor, which configure an inverter is designed to optimize the efficiency at any of frequency bands. The frequency band of the input signal is split, and each of the split outputs is input to a DCDC converter element that has a corresponding frequency and high efficiency characteristic.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: June 7, 2011
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Takashi Kawamoto, Takashi Oshima, Taizo Yamawaki, Manabu Nakamura
  • Publication number: 20110128171
    Abstract: In the digital calibration technique of the conventional time-interleaved analog/digital converter, it is impossible to perform highly-accurate calibration that supports a high-speed sampling rate of the next-generation application and achieves a high resolution. For its solution, a reference A/D conversion unit is connected in parallel to an input common to a time-interleaved A/D converter to be a calibration target, and the output of each unitary A/D conversion unit which makes up the time-interleaved A/D converter is calibrated in a digital region by using a low-speed high-resolution A/D conversion result output from the reference A/D conversion unit. Also, fCLK/N (fCLK represents an overall sampling rate of the time-interleaved A/D converter, and N is relatively prime to the number of unitary A/D conversion units connected in parallel M) is set as the operation clock frequency of the reference A/D conversion unit.
    Type: Application
    Filed: February 19, 2009
    Publication date: June 2, 2011
    Inventors: Takashi Oshima, Taizo Yamawaki, Tomomi Takahashi
  • Patent number: 7917690
    Abstract: Each of a plurality of memory areas includes a plurality of blocks. Each of the blocks includes a plurality of pages. Each of the memory areas also includes a data cache and a page buffer. A control unit controls a lower-limit value of the number of empty blocks in each of the plurality of memory areas.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: March 29, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Oshima
  • Patent number: 7898862
    Abstract: A semiconductor device includes a transfer section which receives, from an external source, a second program for modifying a function of a first program stored in a read-only memory (ROM) and information required in activation of the second program, and which writes the program and the information to a nonvolatile semiconductor memory, and a load section which activates the second program on the basis of the information written to the nonvolatile semiconductor memory to modify the function of the first program.
    Type: Grant
    Filed: November 27, 2009
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tetsuya Murakami, Takashi Oshima
  • Publication number: 20100325467
    Abstract: A memory system, which is connected to a host device, includes a memory, a host interface which receives a command and an address, which are output from the host device, and a controller which operates in one of a first mode in which the controller converts the address which is received by the host interface and accesses the memory by using the converted address, and a second mode in which the host device directly accesses the memory by using the address which is received by the host interface, the controller controlling switching between the first mode and second mode in accordance with the command.
    Type: Application
    Filed: August 6, 2010
    Publication date: December 23, 2010
    Inventors: Takashi OSHIMA, Makoto MORIYA
  • Patent number: 7843369
    Abstract: In a wireless transmitter and receiver, a background calibration type analog-to-digital converter generally occupies a large area because of the phase compensating capacity of an op-amp included in a reference analog-to-digital conversion unit. Further, the calibration type analog-to-digital converter generally requires a sample and hold circuit to exclude influence of parasitic capacitance of wirings, thereby increasing power consumption. Digital calibration is performed by using, as a signal for calibration, an input signal of a digital-to-analog converter in a transmitter circuit of the wireless transmitter and receiver and inputting an output signal from the digital-to-analog converter to the analog-to-digital converter in the receiver circuit.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: November 30, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Tomomi Takahashi, Takashi Oshima, Taizo Yamawaki
  • Patent number: 7814264
    Abstract: A semiconductor device includes a controller which operates if a request is made that data be written in a certain area in a first block in a semiconductor memory having a predetermined erase block size in which data has already been written, to write the data requested to be written, in a leading area in a second block from which data has already been erased, regardless of a value of an address of the certain area.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: October 12, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Oshima
  • Publication number: 20100241677
    Abstract: In response to an instruction to read/write data from a host device 2 employing a FAT file system that uses multiplexed file management information including a FAT 5a and a FAT 5b as backup information, a controller 11 that constitutes a memory system 1 including a NAND flash memory 12 as a non-volatile area uses a FAT 18 as file management information that does not include the backup information to handle the reading/writing of data.
    Type: Application
    Filed: September 3, 2008
    Publication date: September 23, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takashi Oshima, Chikara Kondo
  • Patent number: 7793035
    Abstract: A memory system, which is connected to a host device, includes a memory, a host interface which receives a command and an address, which are output from the host device, and a controller which operates in one of a first mode in which the controller converts the address which is received by the host interface and accesses the memory by using the converted address, and a second mode in which the host device directly accesses the memory by using the address which is received by the host interface, the controller controlling switching between the first mode and second mode in accordance with the command.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: September 7, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Oshima, Makoto Moriya
  • Patent number: 7764216
    Abstract: In an analog-to-digital converter, when a capacitive element with a small capacitance is used in order to reduce power consumption, the characteristics of the analog-to-digital converter deteriorate due to the variation in the specific accuracy. Further, the method of reducing the variation with the specific accuracy causes an increase in the size of the circuit and power consumption. An analog-to-digital converter includes an analog core unit having at least one capacitive element. The capacitive element includes a capacitive bank having plural capacitive element units having substantially the same capacitance value, and the capacitive bank is configured to select one capacitive element unit from the plural capacitive element units with substantially equal probability.
    Type: Grant
    Filed: July 11, 2008
    Date of Patent: July 27, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Oshima, Taizo Yamawaki