Patents by Inventor Ichiro Fujimori

Ichiro Fujimori 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: 6911855
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: June 28, 2005
    Assignee: Broadcom Corporation
    Inventors: Guangming Yin, Ichiro Fujimori, Armond Hairapetian
  • Patent number: 6909332
    Abstract: The present invention provides a method for tuning output drivers to an operating frequency based on settings used to tune other devices within the device such as a VCO. First the VCO within a PLL and clock circuit is tuned to the desired operating frequency. This operating frequency then corresponds to a discrete tuning setting. The discrete setting that causes the VCO to function at the operating frequency are then transferred to scaled amplifiers within output drivers. These drivers are then tuned to the operating frequency with these settings. This process eliminates the need to individually tune each output driver to function properly at the operating frequency.
    Type: Grant
    Filed: August 12, 2003
    Date of Patent: June 21, 2005
    Assignee: Broadcom, Corp.
    Inventors: Guangming Yin, Bo Zhang, Ichiro Fujimori
  • Publication number: 20050124098
    Abstract: Certain aspects of a method for reducing noise disturbing at least one signal in an electronic device may comprise shielding a first layer doped with a first dopant from a signaling layer employing a second layer doped with a second dopant. A first signaling component of the signaling layer may be coupled to the second layer and a second signaling component of the signaling layer may be coupled to the second layer. The second layer may be coupled to the first layer, and this reduces the signal disturbing noise in the electronic device. Shielding the first layer from the signaling layer may comprise disposing the second layer between the first layer and the signaling layer. Shielding the first layer from the signaling layer may comprise disposing a deep N-well between the first layer and the signaling layer.
    Type: Application
    Filed: January 7, 2005
    Publication date: June 9, 2005
    Inventor: Ichiro Fujimori
  • Patent number: 6897697
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: May 24, 2005
    Assignee: Broadcom Corporation
    Inventors: Guangming Yin, Ichiro Fujimori, Armond Hairapetian
  • Publication number: 20050095805
    Abstract: Disclosed herein is a system adapted to reduce noise in a substrate of a chip. The chip may include a substrate having a first well disposed there atop. The first well may be a deep well. A second well and a third may also be disposed within the first well. A first transistor may be disposed in the second well. A quiet voltage source may be connected to a body of the first transistor. A second transistor may be disposed in the third well. The first transistor may be a PMOS transistor and the second transistor may be an NMOS transistor. A noisy voltage source may be coupled to a source of the first transistor. A body of the first transistor may be resistively coupled to the second well.
    Type: Application
    Filed: November 12, 2004
    Publication date: May 5, 2005
    Inventor: Ichiro Fujimori
  • Patent number: 6870228
    Abstract: A system and method for reducing noise in a substrate of a chip is provided. The system may include a substrate (70) doped with a first dopant. A first well (80) may be disposed on the substrate and doped with a second dopant. A second well (120) may be disposed within the first well (80) and doped with the second kind of dopant. A first transistor (100) may include one or more first transistor components disposed in the second well (120). The first transistor (100) may be adapted to employ a first type of channel having a quiet voltage source (140) connected to a body thereof. A third well (110) may be disposed within the first well (80) and doped with the first kind of dopant. A second transistor (90) may include one or more second transistor components that may be disposed in the third well (110). The second transistor (90) may be adapted to employ a second type of channel. The first well (80) may shield the substrate (70) from noise in the second well (120) and third well (110).
    Type: Grant
    Filed: November 14, 2002
    Date of Patent: March 22, 2005
    Assignee: Broadcom Corporation
    Inventor: Ichiro Fujimori
  • Patent number: 6844226
    Abstract: Aspects of the method for reducing noise in the substrate may comprise doping a substrate with a first dopant and doping a first well disposed on the substrate with a second dopant. The first well may be a deep well. A second well disposed within the first well may be doped with a second dopant. A first transistor having a first transistor channel type and one or more transistor components may be disposed within the second well. A quiet voltage source may be coupled to a body of the first transistor. A third well disposed within the first well may be doped with the first dopant. A second transistor having a second transistor type and one or more transistor components may be disposed within the third well. In this arrangement, disposing the first well between the substrate and the second well may reduce noise in the substrate.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: January 18, 2005
    Assignee: Broadcom Corporation
    Inventor: Ichiro Fujimori
  • Publication number: 20040227544
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.
    Type: Application
    Filed: June 25, 2004
    Publication date: November 18, 2004
    Inventors: Guangming Yin, Ichiro Fujimori, Armond Hairapetian
  • Publication number: 20040173852
    Abstract: Certain embodiments of the invention may be found in, for example, a system that reduces noise in a substrate of a chip and may comprise a substrate layer that is integrated within the chip. A transistor layer is integrated within the chip and is shielded from the substrate layer by a shielding layer. At least one transistor of a first transistor type couples the transistor layer to the shielding layer and a quiet voltage source may be coupled to the transistor of the first transistor type. At least one transistor of a second transistor type is coupled to the shielding layer. The transistor of the second transistor type may be a n-type transistor, which may be disposed within the transistor layer and the transistor of the second transistor type may be resistively coupled to the shielding layer.
    Type: Application
    Filed: March 15, 2004
    Publication date: September 9, 2004
    Inventor: Ichiro Fujimori
  • Publication number: 20040173853
    Abstract: Certain embodiments of the invention may be found in, for example, a system that reduces noise in a substrate of a chip and may comprise a substrate and a first well disposed on top of the substrate. The first well may be a deep well. Notwithstanding, a second well and a third are both disposed within the first well and a first transistor may be disposed in the second well. A quiet voltage source may be connected to a body of the first transistor and a second transistor may be disposed in the third well. The first transistor may be a PMOS transistor and the second transistor may be an NMOS transistor. A noisy voltage source may be coupled to a source of the first transistor and a body of the first transistor may be resistively coupled to the second well.
    Type: Application
    Filed: March 15, 2004
    Publication date: September 9, 2004
    Inventor: Ichiro Fujimori
  • Publication number: 20040105410
    Abstract: An apparatus and method are disclosed to aid a transceiver chip, in a wide-band serial data communications system, in receiving data at multiple data rates. A multi-rate filter within the transceiver chip is implemented as at least one adjustable-rate filter stage and a limiting stage. The at least one adjustable-rate filter stage is used to generate a filtered serial data signal from a received serial data signal. The limiter stage generates a full-swing serial data signal from the filtered serial data signal. A bandwidth of the at least one adjustable-rate filter stage is adjustable in order to receive serial data signals at multiple data rates. The bandwidth of the multi-rate filter within the transceiver chip is selectable by the user of the wide-band communication system.
    Type: Application
    Filed: November 19, 2002
    Publication date: June 3, 2004
    Inventors: Ichiro Fujimori, Mario Caresosa, Namik Kocaman
  • Publication number: 20040106263
    Abstract: Aspects of the method for reducing noise in the substrate may comprise doping a substrate with a first dopant and doping a first well disposed on the substrate with a second dopant. The first well may be a deep well. A second well disposed within the first well may be doped with a second dopant. A first transistor having a first transistor channel type and one or more transistor components may be disposed within the second well. A quiet voltage source may be coupled to a body of the first transistor. A third well disposed within the first well may be doped with the first dopant. A second transistor having a second transistor type and one or more transistor components may be disposed within the third well. In this arrangement, disposing the first well between the substrate and the second well may reduce noise in the substrate.
    Type: Application
    Filed: November 12, 2003
    Publication date: June 3, 2004
    Inventor: Ichiro Fujimori
  • Publication number: 20040066867
    Abstract: Apparatus and method are disclosed for constructing an eye pattern from a serial data signal within a receiver used in a serial data communication system. The receiver is used to receive the serial data signal and generates an internal clock signal from the serial data signal using, at least in part, a CDR circuit. Timing data corresponding to a current phase of the clock signal is also generated within the receiver using an interpolator circuit. The serial data signal is sampled by an ADC using the clock signal to generate sampled data. The sampled data and timing data are processed within the receiver by a data processor to generate the eye pattern. The resultant eye pattern may be analyzed within the receiver with respect to at least one characteristic of the eye pattern. At least one parameter of the receiver may be adjusted in response to the foregoing analysis.
    Type: Application
    Filed: January 29, 2003
    Publication date: April 8, 2004
    Inventors: Ichiro Fujimori, Mohammad Sarhang Nejad
  • Publication number: 20040032351
    Abstract: The present invention provides a method for tuning output drivers to an operating frequency based on settings used to tune other devices within the device such as a VCO. First the VCO within a PLL and clock circuit is tuned to the desired operating frequency. This operating frequency then corresponds to a discrete tuning setting. The discrete setting that causes the VCO to function at the operating frequency are then transferred to scaled amplifiers within output drivers. These drivers are then tuned to the operating frequency with these settings. This process eliminates the need to individually tune each output driver to function properly at the operating frequency.
    Type: Application
    Filed: August 12, 2003
    Publication date: February 19, 2004
    Inventors: Guangming Yin, Bo Zhang, Ichiro Fujimori
  • Publication number: 20040028158
    Abstract: Aspects of the invention may provide a method and system for adjusting a gain and/or a frequency response of an input signal for a multimode PHY device. A signal divider (704) may apportion the input signal into a gain adjustment signal and/or an equalization adjustment signal upon receipt of the input signal. A signal adjuster (702) coupled to the signal divider (704) may adjust a gain of the apportioned gain adjustment signal within the multimode PHY device (130). An equalizer (706) coupled to the signal divider (704) may be configured to equalize the equalization adjustment signal within the multimode PHY device (130). A summer (708) coupled to the equalizer (706) and signal adjuster (702) may be adapted to sum the adjusted adjustment signal and the equalized equalization adjustment signal within the multimode PHY device (130) to create an output equalized signal (712) having a desired gain and/or frequency response.
    Type: Application
    Filed: January 7, 2003
    Publication date: February 12, 2004
    Inventors: Ichiro Fujimori, Davide Tonietto
  • Publication number: 20040028065
    Abstract: A bit stream multiplexer includes an input ordering block, a plurality of multiplexers, an output ordering block, and a Pseudo Random Bit Stream (PRBS) function. The input ordering block is operates to receive a first plurality of transmit bit streams at a first bit rate, order the first plurality of transmit bit streams based upon a first order select signal, and produce a first plurality of ordered transmit bit streams at the first bit rate. The input ordering block may also deskew the first plurality of transmit bit streams. The plurality of multiplexers operate to receive the first plurality of ordered transmit bit streams at the first bit rate and produce an interface plurality of transmit bit streams at an interface bit rate. The output ordering block operates to order the interface plurality of transmit bit streams based upon an interface order select signal. The PRBS function produces a PRBS that is coupled to at least one of the interface plurality of transmit bit streams.
    Type: Application
    Filed: January 23, 2003
    Publication date: February 12, 2004
    Inventors: Daniel Schoch, Ichiro Fujimori
  • Publication number: 20040026722
    Abstract: A system and method for reducing noise in a substrate of a chip is provided. The system may include a substrate (70) doped with a first dopant. A first well (80) may be disposed on the substrate and doped with a second dopant. A second well (120) may be disposed within the first well (80) and doped with the second kind of dopant. A first transistor (100) may include one or more first transistor components disposed in the second well (120). The first transistor (100) may be adapted to employ a first type of channel having a quiet voltage source (140) connected to a body thereof. A third well (110) may be disposed within the first well (80) and doped with the first kind of dopant. A second transistor (90) may include one or more second transistor components that may be disposed in the third well (110). The second transistor (90)may be adapted to employ a second type of channel. The first well (80) may shield the substrate (70) from noise in the second well (120) and third well (110).
    Type: Application
    Filed: November 14, 2002
    Publication date: February 12, 2004
    Inventor: Ichiro Fujimori
  • Publication number: 20040030805
    Abstract: A system and method are disclosed for supporting 10 Gigabit digital serial communications. Many of the functional components and sublayers of a 10 Gigabit digital serial communications transceiver module are integrated into a single IC chip using the same CMOS technology throughout the single chip. The single chip includes a PMD transmit/receive CMOS sublayer, a PMD PCS CMOS sublayer, a XGXS PCS CMOS sublayer, and a XAUI transmit/receive CMOS sublayer. The single chip supports both 10 Gigabit Ethernet operation and 10 Gigabit Fibre Channel operation. The single chip interfaces to a MAC, an optical PMD, and non-volatile memory.
    Type: Application
    Filed: October 29, 2002
    Publication date: February 12, 2004
    Inventors: Ichiro Fujimori, Tuan Hoang, Ben Tan, Lorenzo Longo
  • Publication number: 20030067337
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.
    Type: Application
    Filed: June 21, 2002
    Publication date: April 10, 2003
    Applicant: Broadcom Corporation
    Inventors: Guangming Yin, Ichiro Fujimori, Armond Hairapetian
  • Patent number: 6522277
    Abstract: A circuit, system, and method are provided for imparting improved randomness into the selection of components or elements of a data converter, such as a D/A converter. The elements are intended to be of equal value, however, regardless of whether they are or not. A circuit is used to randomly select subsets of elements according to a bi-directional selection technique in order to effectively rending the elements or components of equal value. Associated with each component is a switch, and a subset of the plurality of components are correspondingly switched in successive order progressing in a first direction and, subsequently, in successive order progressing in a second direction opposite the first direction. Connecting components in a first direction from left-to-right follows by selecting components in a second direction from right-to-left, and then again selecting components in the first direction from left-to-right, and so forth.
    Type: Grant
    Filed: February 5, 2001
    Date of Patent: February 18, 2003
    Assignees: Asahi Kasei Microsystems, Inc., Broadcom Corporation
    Inventors: Ichiro Fujimori, Armond Hairapetian, Lorenzo Longo