Patents by Inventor Brett A. Miwa

Brett A. Miwa 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).

  • Publication number: 20190260376
    Abstract: A current sense device includes a reference transistor for electrically coupling to a power transistor, a sense transistor for electrically coupling to the power transistor, and control circuitry. The control circuitry is configured to (a) control current through the sense transistor such that a voltage at the sense transistor has a predetermined relationship to a voltage at the power transistor, and (b) control current through the sense transistor according to one or more operating conditions at the reference transistor, to compensate for aging of the power transistor.
    Type: Application
    Filed: February 20, 2019
    Publication date: August 22, 2019
    Inventors: Marco A. Zuniga, Michael David McJimsey, Brett A. Miwa, Chi-Teh Chiang, Ilija Jergovic, Urs Harald Mader
  • Publication number: 20190252980
    Abstract: A multiphase DC-DC converter includes a coupled inductor, N phases of the multiphase DC-DC converter, and a controller, where N is an integer greater than 2. The coupled inductor includes a plurality of inductors. Each inductor is coupled to two neighboring inductors or to rest of the inductors. The N phases of the multiphase DC-DC converter are respectively connected to the plurality of inductors. The controller operates the multiphase DC-DC converter in continuous conduction mode and in discontinuous conduction mode. Body diodes of switches in the N phases do not conduct when the multiphase DC-DC converter operates in discontinuous conduction mode.
    Type: Application
    Filed: April 18, 2019
    Publication date: August 15, 2019
    Inventors: Xin ZHOU, Justin Michael BURKHART, Brett A. MIWA
  • Patent number: 10326369
    Abstract: A converter includes first and second coupled inductors. A first phase includes first high side and low side switches connected to the first inductor. A second phase includes second high side and low side switches connected to the second inductor. In discontinuous conduction mode, the controller determines, in response to the first high side switch being turned on and the second low side switch being turned off, that coupling between the first and second inductors is strong or weak based on whether body diode of the second low side switch will conduct if not prevented from conducting. The controller prevents second low side switch body diode conduction in response to the first high side switch being turned on when the coupling is strong, and does not prevent second low side switch body diode conduction in response to the first high side switch being turned on when the coupling is weak.
    Type: Grant
    Filed: May 7, 2018
    Date of Patent: June 18, 2019
    Assignee: MAXIM INTEGRATED PRODUCTS, INC.
    Inventors: Xin Zhou, Justin Michael Burkhart, Brett A. Miwa
  • Patent number: 10256031
    Abstract: A low-profile coupled inductor includes a magnetic core and first and second windings. The magnetic core includes first and second end flanges, a winding form element, a first outer plate, and a first leakage post. The winding form element is disposed between and connects the first and second end flanges in a first direction. The first outer plate is disposed over and faces the first and second end flanges in a second direction. The first leakage post is disposed between the winding form element and the first outer plate in the second direction. The first winding is wound around the winding form element, between the first end flange and the first leakage post, and the second winding is wound around the winding form element, between the first leakage post and the second end flange. Each of the windings is wound around a common axis extending in the first direction.
    Type: Grant
    Filed: April 5, 2018
    Date of Patent: April 9, 2019
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Michael Warren Baker, Jizheng Qiu, Brett A. Miwa, Alexandr Ikriannikov
  • Patent number: 10141832
    Abstract: In various embodiments described in the present disclosure, various methods and systems are introduced, that may reduce and/or eliminate the voltage spikes on the power switches by avoiding operation at zero-ripple duty ratios.
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: November 27, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Nenad Vukadinovic, Aleksandar Prodic, Cory Brent Arnold, Brett A. Miwa, Michael Warren Baker
  • Publication number: 20180337602
    Abstract: A method for discontinuous conduction mode operation of a multi-phase DC-to-DC converter includes (a) forward biasing a first inductor being magnetically coupled to a second inductor, (b) reverse biasing the first inductor after forward biasing the first inductor, (c) while reverse biasing the first inductor and before magnitude of current through the first inductor falls to zero, forward biasing the second inductor.
    Type: Application
    Filed: May 16, 2018
    Publication date: November 22, 2018
    Inventors: Xin Zhou, Justin Michael Burkhart, Michael Warren Baker, Brett A. Miwa
  • Publication number: 20180254708
    Abstract: A converter includes first and second coupled inductors. A first phase includes first high side and low side switches connected to the first inductor. A second phase includes second high side and low side switches connected to the second inductor. In discontinuous conduction mode, the controller determines, in response to the first high side switch being turned on and the second low side switch being turned off, that coupling between the first and second inductors is strong or weak based on whether body diode of the second low side switch will conduct if not prevented from conducting. The controller prevents second low side switch body diode conduction in response to the first high side switch being turned on when the coupling is strong, and does not prevent second low side switch body diode conduction in response to the first high side switch being turned on when the coupling is weak.
    Type: Application
    Filed: May 7, 2018
    Publication date: September 6, 2018
    Applicant: Maxim Integrated Products, Inc.
    Inventors: Xin ZHOU, Justin Michael Burkhart, Brett A. Miwa
  • Publication number: 20180226186
    Abstract: A low-profile coupled inductor includes a magnetic core and first and second windings. The magnetic core includes first and second end flanges, a winding form element, a first outer plate, and a first leakage post. The winding form element is disposed between and connects the first and second end flanges in a first direction. The first outer plate is disposed over and faces the first and second end flanges in a second direction. The first leakage post is disposed between the winding form element and the first outer plate in the second direction. The first winding is wound around the winding form element, between the first end flange and the first leakage post, and the second winding is wound around the winding form element, between the first leakage post and the second end flange. Each of the windings is wound around a common axis extending in the first direction.
    Type: Application
    Filed: April 5, 2018
    Publication date: August 9, 2018
    Inventors: Michael Warren Baker, Jizheng Qiu, Brett A. Miwa, Alexandr Ikriannikov
  • Patent number: 10038365
    Abstract: A control circuit for a step-up converter includes a soft start module configured to control states of N transistor pairs of the step-up converter, where N is an integer greater than two. A driver module is in communication with the soft start module and configured to generate a first signal when N transistor pairs of the step-up converter are ready to switch. A first charging circuit is configured to charge (N-1) capacitors of the step-up converter to an input voltage of the step-up converter in response to the first signal and to generate a second signal when charging is complete. A second charging circuit is configured to sequentially charge the (N-1) capacitors of the step-up converter to (N-1) predetermined voltage values in response to the first signal and the second signal and before operation of the step-up converter begins.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: July 31, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Serhii Mikhailovich Zhak, Mark Anthony Belch, Brett A. Miwa, David Harrington, Jonathan King
  • Publication number: 20180205307
    Abstract: In various embodiments described in the present disclosure, various methods and systems are introduced, that may reduce and/or eliminate the voltage spikes on the power switches by avoiding operation at zero-ripple duty ratios.
    Type: Application
    Filed: July 11, 2016
    Publication date: July 19, 2018
    Inventors: Nenad Vukadinovic, Aleksandar Prodic, Cory Brent Arnold, Brett A. Miwa, Michael Warren Baker
  • Patent number: 9966853
    Abstract: The present disclosure eliminates the unwanted conduction of the body diode of the low side switch or the unwanted conduction of the low side switch in coupled phases of DC-DC converters operating in DCM to increase efficiency. Specifically, in one implementation, by detecting strong or weak coupling, the present disclosure eliminates body diode conduction in strong coupling by turning on the low side switch and eliminates negative body diode current in weak coupling by turning off the low side switch. Further, for multiphase switching DC-DC converters with coupled inductors operating at light load (i.e., in DCM), when a high side switch of a first phase is turned on, the body diode of a low side switch of a second phase is adaptively bypassed if needed, blocked by specific design, or prevented from conducting by reducing forward voltage across the body diode.
    Type: Grant
    Filed: October 3, 2016
    Date of Patent: May 8, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Xin Zhou, Justin Michael Burkhart, Brett A. Miwa
  • Patent number: 9893622
    Abstract: A multi-level, step-up converter circuit includes an inductor including one terminal in communication with an input voltage supply. N transistor pairs are connected in series, where N is an integer greater than one. First and second transistors of a first pair of the N transistor pairs are connected together at a node. The node is in communication with another terminal of the inductor. Third and fourth transistors of a second pair of the N transistor pairs are connected to the first and second transistors, respectively. (N?1) capacitors have terminals connected between the N transistor pairs, respectively. An output capacitor has a terminal in communication with at least one transistor of the N transistor pair.
    Type: Grant
    Filed: May 12, 2017
    Date of Patent: February 13, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Serhii Mikhailovich Zhak, Mark Anthony Belch, Brett A. Miwa, David Harrington, Jonathan King
  • Patent number: 9882483
    Abstract: A method of regulating voltage includes closing first and second switching devices during first and second periods in response to first and second signals, respectively. The first and second switching devices open and close to connect and disconnect first ends of first and second inductors of first and second phases of a voltage regulator to and from an input voltage, respectively. The method includes selectively generating one of the first and second signals when a third signal is in a first state; selectively setting the third signal to the first state based on a ramp voltage; resetting the ramp voltage to a predetermined reset voltage when the third signal transitions from a second state to the first state; maintaining the ramp voltage at the predetermined reset voltage for a predetermined ramp reset period after the resetting; and increasing the ramp voltage after the predetermined ramp reset period.
    Type: Grant
    Filed: November 7, 2016
    Date of Patent: January 30, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Serhii M. Zhak, Brett A. Miwa
  • Publication number: 20170250607
    Abstract: A multi-level, step-up converter circuit includes an inductor including one terminal in communication with an input voltage supply. N transistor pairs are connected in series, where N is an integer greater than one. First and second transistors of a first pair of the N transistor pairs are connected together at a node. The node is in communication with another terminal of the inductor. Third and fourth transistors of a second pair of the N transistor pairs are connected to the first and second transistors, respectively. (N?1) capacitors have terminals connected between the N transistor pairs, respectively. An output capacitor has a terminal in communication with at least one transistor of the N transistor pair.
    Type: Application
    Filed: May 12, 2017
    Publication date: August 31, 2017
    Inventors: Serhii Mikhailovich ZHAK, Mark Anthony Belch, Brett A. Miwa, David Harrington, Jonathan King
  • Publication number: 20170237336
    Abstract: A control circuit for a step-up converter includes a soft start module configured to control states of N transistor pairs of the step-up converter, where N is an integer greater than two. A driver module is in communication with the soft start module and configured to generate a first signal when N transistor pairs of the step-up converter are ready to switch. A first charging circuit is configured to charge (N-1) capacitors of the step-up converter to an input voltage of the step-up converter in response to the first signal and to generate a second signal when charging is complete. A second charging circuit is configured to sequentially charge the (N-1) capacitors of the step-up converter to (N-1) predetermined voltage values in response to the first signal and the second signal and before operation of the step-up converter begins.
    Type: Application
    Filed: March 24, 2017
    Publication date: August 17, 2017
    Inventors: Serhii Mikhailovich ZHAK, Mark Anthony BELCH, Brett A. MIWA, David HARRINGTON, Jonathan KING
  • Patent number: 9653986
    Abstract: A multi-level, step-up converter circuit includes an inductor including one terminal in communication with an input voltage supply. N transistor pairs are connected in series, where N is an integer greater than one. First and second transistors of a first pair of the N transistor pairs are connected together at a node. The node is in communication with another terminal of the inductor. Third and fourth transistors of a second pair of the N transistor pairs are connected to the first and second transistors, respectively. (N?1) capacitors have terminals connected between the N transistor pairs, respectively. An output capacitor has a terminal in communication with at least one transistor of the N transistor pair.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: May 16, 2017
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Serhii Mikhailovich Zhak, Mark Anthony Belch, Brett A. Miwa, David Harrington, Jonathan King
  • Publication number: 20170098998
    Abstract: The present disclosure eliminates the unwanted conduction of the body diode of the low side switch or the unwanted conduction of the low side switch in coupled phases of DC-DC converters operating in DCM to increase efficiency. Specifically, in one implementation, by detecting strong or weak coupling, the present disclosure eliminates body diode conduction in strong coupling by turning on the low side switch and eliminates negative body diode current in weak coupling by turning off the low side switch. Further, for multiphase switching DC-DC converters with coupled inductors operating at light load (i.e., in DCM), when a high side switch of a first phase is turned on, the body diode of a low side switch of a second phase is adaptively bypassed if needed, blocked by specific design, or prevented from conducting by reducing forward voltage across the body diode.
    Type: Application
    Filed: October 3, 2016
    Publication date: April 6, 2017
    Inventors: Xin ZHOU, Justin Michael BURKHART, Brett A. MIWA
  • Patent number: 9608512
    Abstract: A control circuit for a step-up converter includes a soft start module configured to control states of N transistor pairs of the step-up converter, where N is an integer greater than two. A driver module is in communication with the soft start module and configured to generate a first signal when N transistor pairs of the step-up converter are ready to switch. A first charging circuit is configured to charge (N?1) capacitors of the step-up converter to an input voltage of the step-up converter in response to the first signal and to generate a second signal when charging is complete. A second charging circuit is configured to sequentially charge the (N?1) capacitors of the step-up converter to (N?1) predetermined voltage values in response to the first signal and the second signal and before operation of the step-up converter begins.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: March 28, 2017
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Serhii Mikhailovich Zhak, Mark Anthony Belch, Brett A. Miwa, David Harrington, Jonathan King
  • Publication number: 20170063234
    Abstract: A method of regulating voltage includes closing first and second switching devices during first and second periods in response to first and second signals, respectively. The first and second switching devices open and close to connect and disconnect first ends of first and second inductors of first and second phases of a voltage regulator to and from an input voltage, respectively. The method includes selectively generating one of the first and second signals when a third signal is in a first state; selectively setting the third signal to the first state based on a ramp voltage; resetting the ramp voltage to a predetermined reset voltage when the third signal transitions from a second state to the first state; maintaining the ramp voltage at the predetermined reset voltage for a predetermined ramp reset period after the resetting; and increasing the ramp voltage after the predetermined ramp reset period.
    Type: Application
    Filed: November 7, 2016
    Publication date: March 2, 2017
    Inventors: Serhii M. Zhak, Brett A. Miwa
  • Patent number: 9490702
    Abstract: A voltage regulator includes at least two phases, where each phase includes an inductor connected at one end to a load, a switching device that opens and closes to connect another end of the inductor to and from an input voltage; and a pulse generator that selectively closes the switching device. A phase manager module selectively triggers a pulse generator to close its switching device for a closed period when a third signal is in a first state. A comparator module selectively sets the third signal to the first state based on a ramp voltage. A ramp generator module maintains the ramp voltage at a predetermined reset voltage for a predetermined ramp reset period after the third signal transitions to the first state. The predetermined ramp reset period is less than a minimum value of the closed period. This allows the switching devices of multiple phases to be closed simultaneously.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: November 8, 2016
    Assignee: Maxim Intergrated Products, Inc.
    Inventors: Serhii M. Zhak, Brett A. Miwa