Patents by Inventor William Lo

William Lo 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: 6999013
    Abstract: A nonlinearity detection system for an analog to digital converter (ADC) comprises a signal generator that generates a periodic signal that is output to the ADC and that comprises first and second intervals. The periodic signal monotonically increases during the first interval and monotonically decreases during the second interval. A differentiator module communicates with the ADC and that generates an output signal that is based on an output of the ADC and a delayed output of the ADC. A nonlinearity detection module detects slope discontinuities in the output signal of the differentiator module.
    Type: Grant
    Filed: July 27, 2005
    Date of Patent: February 14, 2006
    Assignee: Marvell International LTD
    Inventors: Pierte Roo, Francis Campana, William Lo
  • Patent number: 6995551
    Abstract: A physical layer device including a first port, a second port, and a cable that has one end that communicates with the first port and an opposite end that communicates with the second port. A cable tester tests the cable to determine a cable status, which includes an open status, a short status, and a normal status. A pretest module senses activity on the cable and selectively enables testing depending upon the sensed activity. A test module transmits a test pulse on the cable, measures a reflection amplitude, calculates a cable length, and determines the cable status based on the measured amplitude and the calculated cable length. A frequency synthesizer communicates with the cable and that selectively outputs a plurality of signals at a plurality of frequencies on the first port. An insertion loss calculator receives the signals on the second port and that estimates insertion loss.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: February 7, 2006
    Assignee: Marvell International Ltd.
    Inventors: William Lo, Yiqing Guo, Tak Tsui, Tsin-Ho Leung, Runsheng He, Eric Janofsky
  • Patent number: 6992491
    Abstract: A cable tester tests cable and determines a cable pass/fail status. A pretest module senses activity on the cable and selectively enables testing based on the sensed activity. A test module is enabled by the pretest module, transmits a test pulse on the cable, measures a reflection amplitude, and calculates a cable length. The cable status includes an open status, a short status, and a normal status. The test module determines the cable status of the cable based on the cable at least one of passing and failing A out of B cable tests. The test module determines the cable status for each of the B tests based on the measured amplitude and the calculated cable length.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: January 31, 2006
    Assignee: Marvell International, Ltd.
    Inventors: William Lo, Yiqing Guo, Tak Tsui, Tsin-Ho Leung, Runsheng He, Eric Janofsky
  • Patent number: 6993667
    Abstract: An energy saving circuit is connected to a receiver of a first physical layer of a first network device. The energy saving device has first and second energy saving modes. In the first energy saving mode, a sense circuit generates a receive signal when connection activity is detected by the receiver. The energy saving circuit powers down the physical layer when the receiver does not detect the connection activity. An autonegotiation circuit powers up the first physical layer and negotiates a connection with a second physical layer of a second network device when the sense circuit generates the receive signal. In a second energy saving mode, a second timer periodically powers a transmitter and generates a link pulse. After the transmitter generates the link pulse, the transmitter is turned off.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: January 31, 2006
    Assignee: Marvell International Ltd.
    Inventor: William Lo
  • Publication number: 20060001669
    Abstract: A self-reparable semiconductor including a graphics processing unit includes a first pixel processor that performs a first function and a first spare pixel processor. The first and first spare pixel processors are functionally interchangeable. Switching devices communicate with the first and first spare pixel processors and replace the first pixel processor with the first spare pixel processor when the first pixel processor is inoperable. A controller identifies at least one inoperable pixel processor and generates configuration data for configuring the switching devices to replace the inoperable pixel processor. Memory that is located on the self-reparable semiconductor stores the configuration data for the switching devices. A second pixel processor is functionally interchangeable with the first and first spare pixel processors. The first spare pixel processor is located one of between the first and second pixel processors or adjacent to one of the first or the second pixel processors.
    Type: Application
    Filed: August 3, 2005
    Publication date: January 5, 2006
    Inventors: Sehat Sutardja, Pantas Sutardja, William Lo
  • Patent number: 6982557
    Abstract: A physical layer device according to some implementations includes a cable tester that generates a test pulse on a cable and that determines a cable status including an open status, a short status, and a normal status. A cable impedance estimator communicates with the cable tester and estimates an impedance of the cable based on a reflection amplitude of the test pulse.
    Type: Grant
    Filed: November 2, 2004
    Date of Patent: January 3, 2006
    Assignee: Marvell International, Ltd.
    Inventors: William Lo, Yiqing Guo, Tak Tsui, Tsin-Ho Leung, Runsheng He, Eric Janofsky
  • Patent number: 6980007
    Abstract: A physical layer device that communicates over a cable comprises a cable tester that determines a cable status, which includes an open status, a short status, and a normal status. The cable tester includes a pretest module that senses activity on the cable and selectively enables testing based on the sensed activity. A test module is enabled by the pretest module, transmits a test pulse on the cable, measures a reflection amplitude, calculates a cable length, and determines the cable status based on the measured amplitude and the calculated cable length. An insertion loss estimator communicates with the cable tester and estimates insertion loss of the cable. A return loss estimator communicates with the cable tester and estimates return loss of the cable based on gain parameters of the physical layer device.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: December 27, 2005
    Assignee: Marvell International Ltd.
    Inventors: William Lo, Yiqing Guo, Tak Tsui, Tsin-Ho Leung, Runsheng He, Eric Janofsky
  • Patent number: 6977507
    Abstract: A system comprises a physical layer device that is adapted to communicate with a cable medium and that includes a first input/output terminal. A first transceiver communicates with the first input/output terminal and the cable medium. A cable tester tests the cable medium and determines a cable status. An indicator communciates with the physical layer device and identifies at least one of link presence, link abscence, link activity, link duplex and or link speed of the first input/output terminal during normal operation. The cable tester also uses the indicator to indicate at least one of cable testing status during the test and/or the cable status after the test.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: December 20, 2005
    Assignee: Marvell International Ltd.
    Inventors: Donald Pannell, William Lo, Yiqing Guo
  • Patent number: 6943712
    Abstract: A nonlinearity detection system and method for an analog to digital converter (ADC) includes a triangular wave generator that generates a triangular wave that is output to the ADC. A differentiator module communicates with the ADC and generates an output signal that is based on an output of the ADC and a delayed output of the ADC. A nonlinearity detection module detects slope discontinuities in the output signal of the differentiator module.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: September 13, 2005
    Assignee: Marvell International Ltd.
    Inventors: Pierte Roo, Francis Campana, William Lo
  • Patent number: 6920132
    Abstract: A network interface which reduces pin count in an MII or GMII system by logically combining certain signals to eliminate redundancies, thereby enabling one external connection or pin to perform the functions previously performed by multiple pins. In particular, the two connections previously used for TX_EN and TX_ER are reduced to a single TX_CTRL connection. Similarly, the three connections for RX_DV, CRS and RX_ER are reduced to a single RX_CTRL connection. The COL connection is also eliminated.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: July 19, 2005
    Assignee: Marvell International Ltd.
    Inventor: William Lo
  • Publication number: 20050146321
    Abstract: A system, apparatus, and method for analyzing photon emission data to discriminate between photons emitted by transistors and photons emitted by background sources. The analysis involves spatial and/or temporal correlation of photon emissions. After correlation, the analysis may further involve obtaining a likelihood that the correlated photons were emitted by a transistor. After correlation, the analysis may also further involve assigning a weight to individual photon emissions as a function of the correlation. The weight, in some instances, reflecting a likelihood that the photons were emitted by a transistor. The analysis may further involve automatically identifying transistors in a photon emission image.
    Type: Application
    Filed: January 20, 2005
    Publication date: July 7, 2005
    Applicant: Credence Systems Corporation
    Inventors: Romain Desplats, Patricia Le Coupanec, William Lo, Philippe Perdu, Steven Kasapi
  • Publication number: 20050073675
    Abstract: A scanned optical system for use in optical probing applications provides a large Field of View (FOV) for objective lenses having high Numerical Aperture (NA), such as Solid Immersion Lenses (SIL's). This enables high resolution imaging of semiconductor devices for such applications as laser probing, TIVA/LIVA, OBIRCH, and photon emission timing analysis. A hybrid scanning optics configuration is disclosed to provide high resolution imaging over a small area along with low resolution imaging over a large area.
    Type: Application
    Filed: October 2, 2003
    Publication date: April 7, 2005
    Inventor: William Lo
  • Publication number: 20050055467
    Abstract: A resynchronization device for an Ethernet network device with a transmitter and a receiver includes a detector that detects faulty code groups received by the receiver. A counter counts the faulty code groups that are detected by the false carrier detector during a predetermined period. A resynchronization trigger asserts a resynchronization signal if the counter exceeds a predetermined threshold during the predetermined period. The faulty code groups include false carriers, which include non-idle code groups other than frame delimiters. Alternately, the faulty code groups include idle code groups that match idle code groups generated by the transmitter of the local network device.
    Type: Application
    Filed: September 9, 2003
    Publication date: March 10, 2005
    Applicant: Marvell International Ltd.
    Inventors: Francis Campana, William Lo
  • Publication number: 20050015660
    Abstract: A self-reparable semiconductor includes multiple functional units that perform the same function and that include sub-functional units. The semiconductor includes one or more full or partial spare functional units that are integrated into the semiconductor. If a defect in a sub-functional unit is detected, then that sub-functional unit is switched out and replaced with a sub-functional unit in the full or partial spare functional unit. The reconfiguration is realized with switching devices that are associated with the sub-functional units. Defective functional or sub-functional units can be detected after assembly, during power up, periodically during operation, and/or manually.
    Type: Application
    Filed: July 16, 2004
    Publication date: January 20, 2005
    Applicant: Marvell World Trade Ltd.
    Inventors: Sehat Sutardja, Pantas Sutardja, William Lo
  • Patent number: 6842481
    Abstract: An arrangement for secure repeater communication in an IEEE 802.3 network by transmitting transmit data and a transmit enable signal on a selected repeater port based on an address lookup table in the repeater core. The other repeater ports that do not have a network address corresponding to the destination address of data packet receive corrupted data generated in response to signals from the respective repeater ports. The repeater ports cause generation of corrupted data by concurrently outputting an asserted transmit error signal and an unasserted transmit enable signal on the corresponding media independent interface. A physical layer transceiver, upon detecting the concurrent assertion of the transmit error signal and the deassertion of the transmit enable signal on the media independent interface, selectively outputs a prescribed data pattern as the transmit data to the network node.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: January 11, 2005
    Assignee: Advanced Micro Devices, Inc.
    Inventor: William Lo
  • Patent number: 6831479
    Abstract: A circuit that reduces external terminal count of a semiconductor chip, such as a communications chip or other type of chip that requires the generation of configuration codes, by reducing the number of external input terminals required for generating the configuration data. The circuit includes multiplexers, each of which selects output data or configuration data, and includes an output in communication with a respective external output terminal of the chip. A selector is connectable between a selected one of the external output terminals and an external input terminal in communication with a memory to serially input configuration data on that output terminal to the memory to configure the chip. Thus, configuration codes are generated for the chip using a reduced number of external input terminals, thereby reducing the overall external terminal count of the chip. The circuit and chip may be embodied on a network or Ethernet card.
    Type: Grant
    Filed: November 5, 2002
    Date of Patent: December 14, 2004
    Assignee: Marvell International Ltd.
    Inventor: William Lo
  • Patent number: 6825672
    Abstract: A cable testing system and method tests cable and determines status, cable length and reflection amplitude. The test module includes a pretest state machine that senses activity on the cable and enables testing if activity is not detected for a first period. A test state machine is enabled by the pretest state machine, transmits a test pulse on the cable, measures a reflection amplitude and calculates a cable length. The test module determines the status based on the measured amplitude and the calculated cable length. A lookup table includes a plurality of sets of reflection amplitudes as a function of cable length. The test module determines the status using the lookup table, the reflection amplitude and the cable length.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: November 30, 2004
    Assignee: Marvell International Ltd.
    Inventors: William Lo, Yiqing Guo
  • Patent number: 6816505
    Abstract: A network device comprises a first integrated circuit having fabricated thereon a media access controller and a first serializer interface in communication with the media access controller. A second integrated circuit is provided comprising a physical layer interface in communication with an external device and a second serializer interface in communication with physical layer interface and the first serializer interface. The first and second serializer interfaces each comprise a fiber channel physical layer device implemented in accordance with 1000 BASE-X.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: November 9, 2004
    Assignee: Marvell International Ltd.
    Inventors: Sehat Sutardja, William Lo
  • Patent number: 6741097
    Abstract: A circuit that reduces external terminal count of a semiconductor chip, such as a communications chip or other type of chip that requires the generation of configuration codes, by reducing the number of external input terminals required for generating the configuration data. The circuit includes multiplexers, each of which selects output data or configuration data, and includes an output in communication with a respective external output terminal of the chip. A selector is connectable between a selected one of the external output terminals and an external input terminal in communication with a memory to serially input configuration data on that output terminal to the memory to configure the chip. Thus, configuration codes are generated for the chip using a reduced number of external input terminals, thereby reducing the overall external terminal count of the chip. The circuit and chip may be embodied on a network or Ethernet card.
    Type: Grant
    Filed: November 5, 2002
    Date of Patent: May 25, 2004
    Assignee: Iarvell International, Ltd.
    Inventor: William Lo
  • Patent number: 6587558
    Abstract: A virtual interactive response (VIR) system mimics and enhances interactive voice response (IVR) technology by using humans to drive the voice recognition unit (VRU) speech recognition functionality. This VIR system initiates a dialogue with the customer by prompting the customer with an initial welcoming message. Calls from a customer are initially made in a first region having high labor costs, but are then directed to an overseas location using voice over Internet protocol (VOIP) or other voice communications technology. The calls are then directed to an appropriate human agent at the overseas location who then listens to the customer's query and makes a decision on how to respond to the customer.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: July 1, 2003
    Assignee: Immequire, LLC
    Inventor: William Lo