Patents by Inventor Jianping Xu

Jianping Xu 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: 6995605
    Abstract: A resonance suppression circuit is provided to suppress resonance on a power grid of a chip or die. The resonance suppression circuit may include a band-pass filter portion, a comparator portion, an amplification portion and a current dissipation portion. The band-pass filter portion may include an inverter coupled between two signal lines of the power grid. The comparator portion may sense voltage fluctuations at approximately the resonance frequency and trigger the current dissipation portion to turn ON and thereby change the frequency spectrum of the load current on the power grid to suppress the power grid resonance.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: February 7, 2006
    Assignee: Intel Corporation
    Inventors: Peter Hazucha, Jianping Xu, Gerhard Schrom, Tanay Karnik, Fabrice Paillet, Vivek K. De
  • Publication number: 20050269586
    Abstract: A light-emitting device and optical communication system based on the light-emitting device is disclosed. The light-emitting device is formed in a float-zone substrate. The light-emitting device includes on the substrate lower surface a reflective layer and on the upper surface spaced apart doped regions. The portion of the upper surface between the doped regions is textured and optionally covered with an antireflection coating to enhance light emission. The light-emitting device can operate as a laser or as a light-emitting diode, depending on the reflectivities of the antireflection coating and the reflective layer.
    Type: Application
    Filed: August 2, 2005
    Publication date: December 8, 2005
    Inventors: Donald Gardner, Tanay Karnik, Jianping Xu, Shekhar Borkar
  • Patent number: 6967515
    Abstract: A circuit to provide a differential signal output in response to a single-ended signal input, the circuit allowing for a wide common-mode input signal by providing complementary amplifier structures.
    Type: Grant
    Filed: March 24, 2004
    Date of Patent: November 22, 2005
    Assignee: Intel Corporation
    Inventors: Fabrice Paillet, David Rennie, Tanay Karnik, Jianping Xu
  • Patent number: 6958640
    Abstract: An apparatus and method for generating signals with improved timing resolution includes a delay cell configured to receive dual coupled differential input signals. The delay cell performs an interpolation function which smooths state transitions or other discontinuities that result from timing or phase offsets between the input signals. The interpolation function is performed by resistors which couple respective components of the differential inputs prior to traversing delay paths. A delay cell of this type has high supply noise rejection and a low output swing range, thereby making it suitable for a number of applications. One application includes a jitter noise generator which uses the delay cell to achieve improved timing resolution and which is not limited by a minimum delay of the cell. Another application uses the delay cell to form a coupled delay line.
    Type: Grant
    Filed: December 31, 2003
    Date of Patent: October 25, 2005
    Assignee: Intel Corporation
    Inventors: KyeHyung Lee, Jianping Xu, Fabrice Paillet, Tanay Karnik
  • Publication number: 20050232637
    Abstract: A laser driver for high speed interconnections may convert a digital signal to a current train of a bias mode to represent logical zero and of a modulation mode to represent logical one. An optical signal thus produced may include an optical offset. An optical receiver may include a photo-detector to receive the optical signal and generate a current signal, which includes a corresponding current offset. A first amplifier stage converts the current signal to a voltage signal and a second amplifier stage generates a digital output from the voltage signal. One or more low-pass filters may be used to filter the digital output and generate a filtered offset signal for a differential amplifier to generate an offset cancellation signal. The offset cancellation signal may be provided to offset cancellation circuitry to remove the current offset from the current signal generated by the photo-detector.
    Type: Application
    Filed: December 30, 2004
    Publication date: October 20, 2005
    Inventors: Fabrice Paillet, Tanay Karnik, Jianping Xu, Donald Gardner
  • Publication number: 20050226279
    Abstract: One embodiment of a laser driver for high speed interconnections includes a buffered level shifter to shift the input voltage level to an appropriate level. In some embodiments the buffered level shifter may be tuned to provide a desired level shift with impedance matched to the driving load. Another embodiment converts a digital signal to a current train of a bias mode to represent logical zero and of a modulation mode to represent logical one, wherein one or both of the bias mode and modulation mode may be adjusted, for example by a programmable control circuit or by an adaptive control circuit. Some embodiments also provide circuitry for reducing overshoot of the output signal.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 13, 2005
    Inventors: Jianping Xu, Fabrice Paillet, Tanay Karnik
  • Publication number: 20050218972
    Abstract: A resonance suppression circuit is provided to suppress resonance on a power grid of a chip or die. The resonance suppression circuit may include a band-pass filter portion, a comparator portion, an amplification portion and a current dissipation portion. The band-pass filter portion may include an inverter coupled between two signal lines of the power grid. The comparator portion may sense voltage fluctuations at approximately the resonance frequency and trigger the current dissipation portion to turn ON and thereby change the frequency spectrum of the load current on the power grid to suppress the power grid resonance.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 6, 2005
    Inventors: Peter Hazucha, Jianping Xu, Gerhard Schrom, Tanay Karnik, Fabrice Paillet, Vivek De
  • Publication number: 20050212559
    Abstract: A circuit to provide a differential signal output in response to a single-ended signal input, the circuit allowing for a wide common-mode input signal by providing complementary amplifier structures.
    Type: Application
    Filed: March 24, 2004
    Publication date: September 29, 2005
    Inventors: Fabrice Paillet, David Rennie, Tanay Karnik, Jianping Xu
  • Patent number: 6924510
    Abstract: A light-emitting device and optical communication system based on the light-emitting device is disclosed. The light-emitting device is formed in a float-zone substrate. The light-emitting device includes on the substrate lower surface a reflective layer and on the upper surface spaced apart doped regions. The portion of the upper surface between the doped regions is textured and optionally covered with an antireflection coating to enhance light emission. The light-emitting device can operate as a laser or as a light-emitting diode, depending on the reflectivities of the antireflection coating and the reflective layer.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: August 2, 2005
    Assignee: Intel Corporation
    Inventors: Donald S. Gardner, Tanay Karnik, Jianping Xu, Shekhar Y. Borkar
  • Publication number: 20050140412
    Abstract: An apparatus and method for generating signals with improved timing resolution includes a delay cell configured to receive dual coupled differential input signals. The delay cell performs an interpolation function which smooths state transitions or other discontinuities that result from timing or phase offsets between the input signals. The interpolation function is performed by resistors which couple respective components of the differential inputs prior to traversing delay paths. A delay cell of this type has high supply noise rejection and a low output swing range, thereby making it suitable for a number of applications. One application includes a jitter noise generator which uses the delay cell to achieve improved timing resolution and which is not limited by a minimum delay of the cell. Another application uses the delay cell to form a coupled delay line.
    Type: Application
    Filed: December 31, 2003
    Publication date: June 30, 2005
    Inventors: KyeHyung Lee, Jianping Xu, Fabrice Paillet, Tanay Karnik
  • Publication number: 20050069070
    Abstract: A system and method for sampling a data stream generates a number of clock signals having equally spaced phases and then samples a data stream using the clock signals. The clock phases are preferably based on a predetermined fraction of a data rate frequency of the data stream, and sampling is performed based on predetermined combinations of the clock signals. While the system and method is suitable for sampling data transmitted for a wide variety of data rates, the system and method is especially well-suited to sampling at data transmitted at high rates, for example, equal to or greater than 20 Gb/s.
    Type: Application
    Filed: September 30, 2003
    Publication date: March 31, 2005
    Inventors: Fabrice Paillet, Tanay Karnik, Jianping Xu
  • Publication number: 20040258419
    Abstract: A method and apparatus for optical signaling. In one embodiment, a laser driver converts a digital voltage sequence to a current signal having a bias mode adjustable by a bias control and a modulation mode adjustable by a modulation control. A laser generates an optical signal responsive to the current signal of the laser driver. In one embodiment, a photo-detector receives an optical signal and generates a single ended current signal. A transimpedance amplifier circuit converts the single ended current signal to a differential voltage signal. A clock recovery circuit generates an aligned clock signal and a sampler circuit uses the aligned clock signal to retrieve a digital voltage sequence.
    Type: Application
    Filed: March 31, 2004
    Publication date: December 23, 2004
    Inventors: Jianping Xu, Fabrice Paillet, Tanay Karnik, Donald S. Gardner
  • Publication number: 20040247266
    Abstract: Connectors, signaling assemblies, circuit boards, and communication systems are disclosed. Some embodiments include signaling media having a plurality of optical and electrical signal conductors.
    Type: Application
    Filed: July 2, 2004
    Publication date: December 9, 2004
    Applicant: Intel Corporation
    Inventors: Tanay Karnik, Jianping Xu
  • Publication number: 20040217373
    Abstract: An integrated circuit die includes optical interconnect ports on a first side and electrical interconnect ports on a second side.
    Type: Application
    Filed: April 30, 2003
    Publication date: November 4, 2004
    Applicant: Intel Corporation
    Inventors: Tanay Karnik, Jianping Xu
  • Publication number: 20040193733
    Abstract: The disclosure describes packet processing techniques that can be used, for example, by a network protocol off-load engine. For example, the techniques may be used in an engine that performs transmission control protocol (TCP) operations for received packets for a host.
    Type: Application
    Filed: September 3, 2002
    Publication date: September 30, 2004
    Inventors: Sriram R. Vangal, Yatin Hoskote, Nitin Y. Borkar, Jianping Xu, Vasantha K. Erraguntla, Shekhar Y. Borkar
  • Publication number: 20040169644
    Abstract: A wireless coordinate input system for a display system includes a stylus that transmits ultrasonic energy to a plurality of ultrasonic receiving stations in a projection plane. In an embodiment, the stylus may include one ultrasonic transmitter used for determination of three-dimensional coordinates of the stylus relative to the projection plane. The stylus may also include a second ultrasonic transmitter controlled by a pressure-activated switch. When the stylus is pressed against the projection plane, the second transmitter turns on and is used for determination of two-dimensional coordinates of the stylus in the projection plane. The stylus may also include a higher frequency burst transmitter used to generate a time reference. One or more of the ultrasonic receiving stations may also include an ultrasonic transmitter for calibration.
    Type: Application
    Filed: March 5, 2004
    Publication date: September 2, 2004
    Applicant: Intel Corporation
    Inventors: Jianping Xu, Stephen H. Hunt
  • Patent number: 6771862
    Abstract: A signaling medium is disclosed. The signaling medium includes several optical media and electrical conductors arranged such that one or more of the electrical conductors are disposed between the optical media. The medium may be shielded, and may included multiple groupings of electrical conductors and optical media. A connector; a signaling assembly, including a signaling medium and connector; a circuit board; and a signal communication system (including multiple circuit boards and one or more signaling media) are also disclosed.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: August 3, 2004
    Assignee: Intel Corporation
    Inventors: Tanay Karnik, Jianping Xu
  • Publication number: 20040125751
    Abstract: The disclosure describes techniques for coordinating operation of multiple network protocol off-load engines (e.g., Transport Control Protocol (TCP) off-load engines).
    Type: Application
    Filed: December 31, 2002
    Publication date: July 1, 2004
    Inventors: Sriram R. Vangal, Yatin Hoskote, Vasantha K. Erraguntla, Jianping Xu
  • Patent number: 6717073
    Abstract: A wireless coordinate input system for a display system includes a stylus that transmits ultrasonic energy to a plurality of ultrasonic receiving stations in a projection plane. The stylus may include one ultrasonic transmitter used for determination of three-dimensional coordinates of the stylus relative to the projection plane. The stylus may also include a second ultrasonic transmitter controlled by a pressure-activated switch. When the stylus is pressed against the projection plane, the second transmitter turns on and is used for determination of two-dimensional coordinates of the stylus in the projection plane. The stylus may also include a higher frequency burst transmitter used to generate a time reference. One or more of the ultrasonic receiving stations may also include an ultrasonic transmitter for calibration.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: April 6, 2004
    Assignee: Intel Corporation
    Inventors: Jianping Xu, Stephen H. Hunt
  • Publication number: 20040044796
    Abstract: In general, in one aspect, the disclosure describes a method for use in tracking received out-of-order packets. Such a method can include receiving at least a portion of a packet that includes data identifying an order within a sequence, and based on the data identifying the order, requesting stored data identifying a set of contiguous previously received out-of-order packets having an ordering within the sequence that borders the received packet.
    Type: Application
    Filed: September 3, 2002
    Publication date: March 4, 2004
    Inventors: Sriram R. Vangal, Yatin Hoskote, Nitin Y. Borkar, Jianping Xu, Vasantha K. Erranguntla, Shekhar Y. Borkar