Patents by Inventor Koichiro Ishibashi

Koichiro Ishibashi 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: 6946865
    Abstract: A semiconductor integrated circuit apparatus includes a first controlled circuit halving at least one MOS transistor and a substrate bias control unit for generating a substrate bias voltage of the MOS transistor, wherein when the substrate bias control unit is set in a first mode, a comparatively large current is allowed to flow between the source and drain of the MOS transistor, while when the substrate bias control unit is set in a second mode, the comparatively large current allowed to flow between the source and drain of the MOS transistor is controlled to a current of smaller value. The value of the substrate bias applied to the first controlled circuit is larger in the second mode than in the first mode for the substrate bias of the PMOS transistor, and smaller in the second mode than in the first mode for the substrate bias of the NMOS transistor. The power supply voltage applied to the first controlled circuit is controlled to a smaller value in the second mode than in the first mode.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: September 20, 2005
    Assignee: Renesas Technology Corporation
    Inventors: Hiroyuki Mizuno, Koichiro Ishibashi, Susumu Narita
  • Patent number: 6943613
    Abstract: A semiconductor integrated circuit device includes control circuits FRQCNT, VDDCNT and VBBCNT that generate the optimum clock signal, supply voltage and substrate bias respectively and then supply them to a main circuit LSI. This operation makes it possible to suppress the variations of a CMOS circuit characteristic, thereby improving the circuit performance. Further, the low power consumption is realized without degrading the operating speed of the CMOS circuit or increasing the power consumption of the CMOS circuit.
    Type: Grant
    Filed: July 13, 2004
    Date of Patent: September 13, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Masayuki Miyazaki, Koichiro Ishibashi
  • Publication number: 20050195041
    Abstract: A semiconductor integrated circuit device comprising a logical circuit including a MIS transistor formed on a semiconductor substrate, a control circuit for controlling a threshold voltage of the MIS transistor forming the logical circuit, an oscillation circuit including a MIS transistor formed on the semiconductor substrate, the oscillation circuit being constructed so that the frequency of an oscillation output thereof can be made variable, and a buffer circuit, in which the control circuit is supplied with a clock signal having a predetermined frequency and the oscillation output of the oscillation circuit so that the control circuit compares the frequency of the oscillation output and the frequency of the clock signal to output a first control signal, the oscillation circuit is controlled by the first control signal so that the frequency of the oscillation output corresponds to the frequency of the clock signal, the control of the frequency of the oscillation output being performed in such a manner that
    Type: Application
    Filed: May 9, 2005
    Publication date: September 8, 2005
    Inventors: Hiroyuki Mizuno, Masataka Minami, Koichiro Ishibashi, Masayuki Miyazaki
  • Patent number: 6940739
    Abstract: A memory structure/circuit has at least two memory cell arrays connected to each other in a hierarchy. The bit lines of the two or more memory cell arrays are connected by hierarchy switches. The memory cells of one of the arrays can be read out faster than the others by using the hierarchy switches to select one array without selecting the other arrays. So the data that is read with higher frequency can be selectively read out faster if it is stored in the faster access memory array. If the data in the faster access memory cell array includes a copy of the data in the other array, it can be used as a cache memory. A tag array and data array in combination that are connected to another tag array and data array in combination through hierarchy switch connections can provide a cache memory that is direct mapped or set associative, and also full associative.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: September 6, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Mizuno, Suguru Tachibana, Koichiro Ishibashi, Kenichi Osada
  • Patent number: 6934923
    Abstract: A semiconductor integrated circuit that is well-balanced between increased operating speed and decreased power consumption caused by a leakage current. The gate cells of the circuit comprised of low threshold voltage MOSs are used for logic gates provided with three or more inputs, and gate cells comprised of high threshold voltage MOSs are generally used for logic gates provided with one or two inputs, sometimes on a case-by-case basis.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: August 23, 2005
    Assignees: Renesas Technology Corporation, Hitachi ULSI Systems Co., Ltd.
    Inventors: Nobuhiro Oodaira, Hiroyuki Mizuno, Yusuke Kanno, Koichiro Ishibashi, Masanao Yamaoka
  • Patent number: 6930504
    Abstract: A semiconductor integrated circuit device is provided which includes a first circuit block connected to a first node and a second circuit block connected to a second node, wherein the second circuit block is provided on the same semiconductor chip as the first circuit block. A comparator is also provided to compare a first potential of the first node and a second potential of the second node. A first supply current in a quiescent state flows through the first node and the first circuit block, and a second supply current in a quiescent state flows through the second node and the second circuit block.
    Type: Grant
    Filed: June 18, 2004
    Date of Patent: August 16, 2005
    Assignee: Renesas Technology Corp.
    Inventor: Koichiro Ishibashi
  • Publication number: 20050174141
    Abstract: The gate tunnel leakage current is increased in the up-to-date process, so that it is necessary to reduce the gate tunnel leakage current in the LSI which is driven by a battery for use in a cellular phone and which needs to be in a standby mode at a low leakage current. In a semiconductor integrated circuit device, the ground source electrode lines of logic and memory circuits are kept at a ground potential in an active mode, and are kept at a voltage higher than the ground potential in an unselected standby mode. The gate tunnel leakage current can be reduced without destroying data.
    Type: Application
    Filed: April 13, 2005
    Publication date: August 11, 2005
    Inventors: Kenichi Osada, Koichiro Ishibashi, Yoshikazu Saitoh, Akio Nishida, Masaru Nakamichi, Naoki Kitai
  • Patent number: 6922094
    Abstract: A data retaining circuit has been disclosed in which, even if a soft error occurs, it is corrected and a normal value can be maintained, the configuration is simple, and high-speed operations are enabled. In this circuit, when a soft error occurs in the data to be put out, it is corrected by a pull-up path or a pull-down path, and when a soft error occurs in the data in the pull-up path or the pull-down path, the error data in the pull-up path or the pull-down path is prevented from affecting each other, as well as turning off the correcting function to prevent the influence on the data to be put out.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: July 26, 2005
    Assignee: Semiconductor Technology Academic Research Center
    Inventors: Yukio Arima, Takahiro Yamashita, Koichiro Ishibashi
  • Patent number: 6922113
    Abstract: The oscillation circuit includes at least two ring oscillation circuits in each of which a plurality of inverters are connected in a ring shape in a multi-stage fashion, and a conductive wiring line. The output of at least one inverter of each of the ring oscillation circuits is connected to the conductive wiring line, whereby the plurality of ring oscillators are caused to oscillate at an identical frequency. A PLL is constructed in such a way that the oscillation circuit obtained by the above means is formed into a voltage-controlled oscillation circuit, and that a phase-frequency comparator, a charge pump circuit and a low-pass filter are employed.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: July 26, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Mizuno, Hirokazu Aoki, Koichiro Ishibashi
  • Publication number: 20050152186
    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: March 7, 2005
    Publication date: July 14, 2005
    Inventors: Koichiro Ishibashi, Shoji Shukuri, Kazumasa Yanagisawa, Junichi Nishimoto, Masanao Yamaoka, Masakazu Aoki
  • Patent number: 6917556
    Abstract: A static memory cell, composed of cross-coupled MOS transistors having a relatively high threshold voltage, is equipped with MOS transistors for controlling the power supply line voltage of the memory cell. To permit the voltage difference between two data storage nodes in the inactivated memory cell to exceed the voltage difference between the two nodes when write data is applied from a data line pair DL and /DL to the two nodes in the activated memory cell, the power supply line voltage control transistors are turned on to apply a high voltage VCH to the power supply lines after the word line voltage is turned off. The data holding voltage in the memory cell can be activated to a high voltage independent of the data line voltage, and the data holding voltage can be dynamically set so that read and write operations can be performed at high speed with low power consumption.
    Type: Grant
    Filed: August 11, 2003
    Date of Patent: July 12, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kiyoo Itoh, Koichiro Ishibashi
  • Publication number: 20050146961
    Abstract: Prior known static random access memory (SRAM) cells are required that a diffusion layer be bent into a key-like shape in order to make electrical contact with a substrate with a P-type well region formed therein, which would result in a decrease in asymmetry leading to occurrence of a problem as to the difficulty in micro-patterning. To avoid this problem, the P-type well region in which an inverter making up an SRAM cell is formed is subdivided into two portions, which are disposed on the opposite sides of an N-type well region NW1 and are formed so that a diffusion layer forming a transistor has no curvature while causing the layout direction to run in a direction parallel to well boundary lines and bit lines. At intermediate locations of an array, regions for use in supplying power to the substrate are formed in parallel to word lines in such a manner that one regions is provided per group of thirty two memory cell rows or sixty four cell rows.
    Type: Application
    Filed: January 26, 2005
    Publication date: July 7, 2005
    Inventors: Kenichi Osada, Masataka Minami, Shuji Ikeda, Koichiro Ishibashi
  • Patent number: 6914803
    Abstract: A logic circuit in a system LSI is provided with a power switch so as to cut off the switch at the time of standby, reducing leakage current. At the same time, an SRAM circuit of the system LSI controls a substrate bias to reduce leakage current.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: July 5, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Masanao Yamaoka, Koichiro Ishibashi, Shigezumi Matsui, Kenichi Osada
  • Patent number: 6906551
    Abstract: A semiconductor integrated circuit device comprising a logical circuit including a MIS transistor formed on a semiconductor substrate, a control circuit for controlling a threshold voltage of the MIS transistor forming the logical circuit, an oscillation circuit including a MIS transistor formed on the semiconductor substrate, the oscillation circuit being constructed so that the frequency of an oscillation output thereof can be made variable, and a buffer circuit, in which the control circuit is supplied with a clock signal having a predetermined frequency and the oscillation output of the oscillation circuit so that the control circuit compares the frequency of the oscillation output and the frequency of the clock signal to output a first control signal, the oscillation circuit is controlled by the first control signal so that the frequency of the oscillation output corresponds to the frequency of the clock signal, the control of the frequency of the oscillation output being performed in such a manner that
    Type: Grant
    Filed: May 28, 2002
    Date of Patent: June 14, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Hiroyuki Mizuno, Masataka Minami, Koichiro Ishibashi, Masayuki Miyazaki
  • Patent number: 6894944
    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: Grant
    Filed: June 25, 2003
    Date of Patent: May 17, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Koichiro Ishibashi, Shoji Shukuri, Kazumasa Yanagisawa, Junichi Nishimoto, Masanao Yamaoka, Masakazu Aoki
  • Patent number: 6885057
    Abstract: The gate tunnel leakage current is increased in the up-to-date process, so that it is necessary to reduce the gate tunnel leakage current in the LSI which is driven by a battery for use in a cellular phone and which needs to be in a standby mode at a low leakage current. In a semiconductor integrated circuit device, the ground source electrode lines of logic and memory circuits are kept at a ground potential in an active mode, and are kept at a voltage higher than the ground potential in an unselected standby mode. The gate tunnel leakage current can be reduced without destroying data.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: April 26, 2005
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Kenichi Osada, Koichiro Ishibashi, Yoshikazu Saitoh, Akio Nishida, Masaru Nakamichi, Naoki Kitai
  • Patent number: 6867637
    Abstract: In a semiconductor integrated circuit device, for realizing high speed, as well as superior product yield rate and usability, while reducing circuit scale and improving on product yield rate and reliability thereof, a main circuit, constructed with CMOS elements, is coupled to a speed monitor circuit for forming a speed signal corresponding to an operating speed thereof and to a substrate bias controller for supplying corresponding substrate bias voltages to the main circuit in response to the speed monitor circuit. A current limiting circuit is also provided in conjunction with the substrate bias controller to prevent an overflow of current due to bias voltage.
    Type: Grant
    Filed: July 13, 2004
    Date of Patent: March 15, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Masayuki Miyazaki, Koichiro Ishibashi, Goichi Ono
  • Patent number: 6864539
    Abstract: A semiconductor integrated circuit device has a MISFET and a body biasing circuit. The MISFET has a source electrode and a drain electrode of a first conductivity type and a gate electrode, and the MISFET is formed in a well of a second conductivity type. The body biasing circuit generates a voltage in the well by passing a prescribed current in a forward direction into a diode which is formed from the well and the source electrode of the MISFET.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: March 8, 2005
    Assignee: Semiconductor Technology Academic Research Center
    Inventors: Koichiro Ishibashi, Takahiro Yamashita
  • Publication number: 20050024917
    Abstract: A memory using an SRAM memory cell intended for low-voltage operation is designed to decrease the threshold value of MOS transistors constituting the memory cell without substantial decrease in the static noise margin, which is the operational margin of the memory cell. To this end, a voltage Vdd? higher than a power supply voltage Vdd of a power supply line for peripheral circuits is supplied from a power supply line for memory cells as a power supply voltage for memory cells. Since the conductance of driver MOS transistors is increased, the threshold voltage of the MOS transistors within the memory cells can be reduced without reducing the static noise margin. Further the ratio of width between the driver MOS transistor and a transfer MOS transistor can be set to 1, thereby allowing a reduction in the memory cell area.
    Type: Application
    Filed: August 26, 2004
    Publication date: February 3, 2005
    Inventors: Masanao Yamaoka, Kenichi Osada, Koichiro Ishibashi
  • Patent number: 6847252
    Abstract: A semiconductor integrated circuit device having a mechanism of compensating not only circuit operational speed but also variations in leakage current, which includes: a main circuit constructed with CMOS device, a delay monitor for simulating a critical path of the main circuit constructed by a CMOS and monitoring a delay of the path, a PN Vt balance compensation circuit for detecting a threshold voltage difference between a PMOS transistor and an NMOS transistor, and a well bias generating circuit for receiving outputs of the delay monitor and the PN Vt balance compensation circuit and applying a well bias to the delay monitor and the main circuit so as to compensate the operation speed of the delay monitor to a desired speed and reduce a threshold voltage difference between the PMOS and NMOS transistors.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: January 25, 2005
    Assignee: Renesas Technology Corporation
    Inventors: Goichi Ono, Masayuki Miyazaki, Koichiro Ishibashi