Patents by Inventor Lawrence A. Prather

Lawrence A. Prather 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: 10205931
    Abstract: A voltage mode laser diode driver selectively turns on and off a laser diode. An output stage has an output node configured to be connected to one of the terminals of the laser diode. Depending upon implementation, an active swing controller drives the output stage in a manner that substantially prevents inductive kickback from causing the output node voltage to swinging above the voltage level at the voltage output of the power supply, or swing below ground. The output stage provides a discharge path around the laser diode to shunt current associated with the inductive kickback, and substantially eliminates ringing on the output node of the output stage while the laser diode is off. A power supply controller adjusts the voltage level of the voltage output of the power supply so that current through the laser diode when on and emitting light is substantially equal to a predetermined desired current.
    Type: Grant
    Filed: March 13, 2017
    Date of Patent: February 12, 2019
    Assignee: MICROSOFT TECHNOLOGY LICENSING, LLC
    Inventors: Barry Thompson, Stefan Wurster, Lawrence A. Prather, Dane Snow, Richard McCauley
  • Patent number: 9769459
    Abstract: A voltage mode laser diode driver selectively turns on and off a laser diode. An output stage has an output node configured to be connected to one of the terminals of the laser diode. Depending upon implementation, an active swing controller drives the output stage in a manner that substantially prevents inductive kickback from causing the output node voltage to swinging above the voltage level at the voltage output of the power supply, or swing below ground. The output stage provides a discharge path around the laser diode to shunt current associated with the inductive kickback, and substantially eliminates ringing on the output node of the output stage while the laser diode is off. A power supply controller adjusts the voltage level of the voltage output of the power supply so that current through the laser diode when on and emitting light is substantially equal to a predetermined desired current.
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: September 19, 2017
    Assignee: MICROSOFT TECHNOLOGY LICENSING, LLC
    Inventors: Barry Thompson, Stefan Wurster, Lawrence A. Prather, Dane Snow, Richard McCauley
  • Publication number: 20170187164
    Abstract: A voltage mode laser diode driver selectively turns on and off a laser diode. An output stage has an output node configured to be connected to one of the terminals of the laser diode. Depending upon implementation, an active swing controller drives the output stage in a manner that substantially prevents inductive kickback from causing the output node voltage to swinging above the voltage level at the voltage output of the power supply, or swing below ground. The output stage provides a discharge path around the laser diode to shunt current associated with the inductive kickback, and substantially eliminates ringing on the output node of the output stage while the laser diode is off. A power supply controller adjusts the voltage level of the voltage output of the power supply so that current through the laser diode when on and emitting light is substantially equal to a predetermined desired current.
    Type: Application
    Filed: March 13, 2017
    Publication date: June 29, 2017
    Applicant: Microsoft Technology Licensing, LLC
    Inventors: Barry Thompson, Stefan Wurster, Lawrence A. Prather, Dane Snow, Richard McCauley
  • Publication number: 20150130903
    Abstract: A voltage mode laser diode driver selectively turns on and off a laser diode. An output stage has an output node configured to be connected to one of the terminals of the laser diode. Depending upon implementation, an active swing controller drives the output stage in a manner that substantially prevents inductive kickback from causing the output node voltage to swinging above the voltage level at the voltage output of the power supply, or swing below ground. The output stage provides a discharge path around the laser diode to shunt current associated with the inductive kickback, and substantially eliminates ringing on the output node of the output stage while the laser diode is off. A power supply controller adjusts the voltage level of the voltage output of the power supply so that current through the laser diode when on and emitting light is substantially equal to a predetermined desired current.
    Type: Application
    Filed: November 12, 2013
    Publication date: May 14, 2015
    Applicant: Microsoft Corporation
    Inventors: Barry Thompson, Stefan Wurster, Lawrence A. Prather, Dane Snow, Richard McCauley
  • Patent number: 7382362
    Abstract: An apparatus and method for processing Hsync and Vsync signals in graphic controllers to avoid a false reading of pulses caused by glitches. The apparatus and method involve detecting when the synch signal crosses the threshold for the first time. When this occurs, the output of the detection circuit is held for the predetermined period of time, even if subsequent transitions across threshold occur during this period. After the predetermined period expires, the output is released and may assume the same state as the input sync signal at that time. In this manner, a misinterpretation of the resolution format caused by the reading of a “false” pulse caused by a glitch on a sync signal can be avoided.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: June 3, 2008
    Assignee: Genesis Microchip Inc.
    Inventors: Ram Chilukuri, Lawrence A. Prather, Ramakrishna R. Venuthurupalli
  • Publication number: 20070290904
    Abstract: Connecting an AC coupled source device to a DC coupled receiver device by way of a connector compatible with the DC coupled device includes generating a signal by the AC coupled source device, transmitting the signal by the AC coupled source device, receiving the signal at a converter unit coupled between the AC coupled source device and the connector, converting the signal to a converted signal suitable for reception by the DC coupled receiver device by the converter unit, passing the converted signal over the connector to the DC coupled receiver unit, and receiving the converted signal by the DC coupled receiver unit.
    Type: Application
    Filed: May 17, 2007
    Publication date: December 20, 2007
    Applicant: Genesis Microchip Inc.
    Inventors: Osamu Kobayashi, Lawrence Prather
  • Publication number: 20050195176
    Abstract: An apparatus and method for processing Hsync and Vsync signals in graphic controllers to avoid a false reading of pulses caused by glitches. The apparatus and method involve detecting when the synch signal crosses the threshold for the first time. When this occurs, the output of the detection circuit is held for the predetermined period of time, even if subsequent transitions across threshold occur during this period. After the predetermined period expires, the output is released and may assume the same state as the input sync signal at that time. In this manner, a misinterpretation of the resolution format caused by the reading of a “false” pulse caused by a glitch on a sync signal can be avoided.
    Type: Application
    Filed: March 3, 2004
    Publication date: September 8, 2005
    Applicant: Genesis Microchip Inc., A Delaware Corporation
    Inventors: Ram Chilukuri, Lawrence Prather, Ramakrishna Venuthurupalli
  • Patent number: 6525586
    Abstract: A programmable delay element is provided for delaying a digital input signal. The programmable delay element comprises a discharge capacitor adapted to be precharged to a predetermined voltage in response to a first transition of the digital input signal. A transistor switch of a first type is provided for precharging the discharge capacitor to a predetermined voltage. A discharge current source is connected via a sense node to the discharge capacitor for discharging the capacitor in response to a subsequent opposite transition of the digital input signal. A transistor switch of a second type is provided for connecting the discharge capacitor to the discharge current source and thereby discharging the discharge capacitor. A reference voltage source is provided for applying a reference voltage to a reference node.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: February 25, 2003
    Assignee: Genesis Microchip, Inc.
    Inventors: Abdullah Ahmed, Sami Bizzan, Lawrence A. Prather