Patents by Inventor Firas Azrai

Firas Azrai 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: 9185767
    Abstract: A self-oscillating resonator (SOR) may be used to control current through light emitting diodes (LEDs). The SOR may be started and stopped by a controller coupled to a transistor switch in the SOR. The controller may output a control signal that starts and stops the SOR by coupling a supply voltage or a ground to a base of the transistor switch in the SOR. Additional control over the current output to the LEDs may be gained through a resistive DAC coupled to the SOR and duty cycling the SOR.
    Type: Grant
    Filed: January 17, 2014
    Date of Patent: November 10, 2015
    Assignee: Cirrus Logic, Inc.
    Inventors: Ramin Zanbaghi, Arnab Kumar Dutta, Firas Azrai
  • Publication number: 20150028768
    Abstract: A turn-off transition time period, also referred to as a reverse recovery time period, may be compensated for by a controller of a power stage including a bipolar junction transistor (BJT). The reverse recovery time period may be measured in one switching cycle and a subsequent switching cycle may include compensations based on the measured reverse recovery time period. That is the switching on and off of the BJT may be compensated to obtain a desired average output current to a load. When the reverse recovery time period is known, an error in the peak current obtained due to the reverse recovery time period may be calculated. The calculated error may be used to offset the target peak current for controlling the switching of the BJT to begin a turn-off transition of the BJT earlier in a switching cycle and thus reduce error in peak current at the BJT.
    Type: Application
    Filed: July 28, 2014
    Publication date: January 29, 2015
    Inventors: John L. Melanson, Thirumalai Rengachari, Siddharth Maru, Ramin Zanbaghi, Firas Azrai, Rahul Singh
  • Publication number: 20140339999
    Abstract: A bipolar junction transistor (BJT) may be used to generate a supply voltage for operating a controller, such as a lighting controller for a LED-based light bulb. A base of the BJT may receive current generated from the supply voltage to control operation of the BJT. Although the base of the BJT would be at a lower voltage than the emitter, a base drive circuit may be coupled between the emitter and the base of the BJT to increase the voltage. As one example, the base drive circuit may be a charge pump. In another example, the BJT may function as its own charge pump. In yet another example, a positive and a negative base current of the BJT may be independently controlled to regulate an output supply voltage VDD from the BJT.
    Type: Application
    Filed: May 16, 2014
    Publication date: November 20, 2014
    Applicant: CIRRUS LOGIC, INC.
    Inventors: John L. Melanson, Ramin Zanbaghi, Jieyeon Choi, Firas Azrai, Rahul Singh, Siddharth Maru
  • Publication number: 20140312797
    Abstract: A self-oscillating resonator (SOR) may be used to control current through light emitting diodes (LEDs). The SOR may be started and stopped by a controller coupled to a transistor switch in the SOR. The controller may output a control signal that starts and stops the SOR by coupling a supply voltage or a ground to a base of the transistor switch in the SOR. Additional control over the current output to the LEDs may be gained through a resistive DAC coupled to the SOR and duty cycling the SOR.
    Type: Application
    Filed: January 17, 2014
    Publication date: October 23, 2014
    Applicant: CIRRUS LOGIC, INC.
    Inventors: Ramin ZANBAGHI, Arnab Kumar DUTTA, Firas AZRAI
  • Publication number: 20100117450
    Abstract: A voltage converter includes a plurality of power conversion circuits that receive respective digital control inputs and supply respective output signals that are separately programmable to have respective desired voltages. A control circuit, a portion of which is shared by the power conversion circuits on a time multiplexed basis, supplies the digital control inputs.
    Type: Application
    Filed: September 4, 2009
    Publication date: May 13, 2010
    Inventors: Firas Azrai, Arthur T. Kimmel, Eric J. King, Eric B. Smith, Michael E. Yates
  • Publication number: 20100060257
    Abstract: A technique for determining an output current of a power converter circuit samples a voltage of a switch node voltage signal at a midpoint of a low phase of the switch node voltage signal and generates a sensed current signal at least partially based on the sampled switch node voltage and a calibration voltage. In at least one embodiment of the invention, an apparatus includes a current sensing circuit configured to generate a sensed current signal indicative of an average output current of a power converter circuit. The sensed current signal is at least partially based on a sample of a voltage signal on a first node of the power converter circuit. The first node is used to supply a current to an inductor of the power converter circuit.
    Type: Application
    Filed: August 31, 2009
    Publication date: March 11, 2010
    Inventors: Firas Azrai, Eric B. Smith
  • Publication number: 20100059795
    Abstract: In at least one embodiment of the invention, an apparatus includes an integrated circuit comprising a power stage portion of a power converter circuit. The power stage portion includes a first switch circuit portion formed by a first plurality of lateral devices in a first substrate. The power stage portion includes a second switch circuit portion formed by a second plurality of lateral devices in the first substrate. The integrated circuit includes a multi-layer current routing structure configured to transport a first current between the first plurality of lateral devices and an array of conductor structures on the surface of the integrated circuit using a first substantially vertical conduction path when the first switch circuit portion is enabled.
    Type: Application
    Filed: September 8, 2008
    Publication date: March 11, 2010
    Inventor: Firas Azrai
  • Patent number: 7239194
    Abstract: A plurality of trenched capacitors are grouped in phases. A control circuit switches each phase between charging and discharging states devised to supply one or more loads with controlled power.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: July 3, 2007
    Assignee: Integral Wave Technologies, Inc.
    Inventors: Firas Azrai, Michael Yates, David Nelms
  • Patent number: 7190210
    Abstract: A plurality of thin-film capacitors are grouped in phases. A control circuit switches each phase between charging and discharging states devised to supply one or more loads with controlled power.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: March 13, 2007
    Assignee: Integral Wave Technologies, Inc.
    Inventors: Firas Azrai, Michael Yates, David Nelms
  • Publication number: 20050213280
    Abstract: A plurality of trenched capacitors are grouped in phases. A control circuit switches each phase between charging and discharging states devised to supply one or more loads with controlled power.
    Type: Application
    Filed: February 28, 2005
    Publication date: September 29, 2005
    Inventors: Firas Azrai, Michael Yates, David Nelms
  • Publication number: 20050213267
    Abstract: A plurality of thin-film capacitors are grouped in phases. A control circuit switches each phase between charging and discharging states devised to supply one or more loads with controlled power.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 29, 2005
    Inventors: Firas Azrai, Michael Yates, David Nelms