Patents by Inventor Michael D Mulligan

Michael D Mulligan 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: 20230387800
    Abstract: A method for operating a DC-DC converter circuit includes, in response to detecting a startup condition, charging an output capacitance coupled to an output node of the DC-DC converter circuit at a first rate in a first phase of a multi-phase startup mode of operation of the DC-DC converter circuit. The method includes, in response to an indication of an output voltage on the output node approaching an input voltage on an input node of the DC-DC converter circuit, controlling a current through an inductor using an oscillating signal in a second phase of the multi-phase startup mode of operation, thereby adjusting the output voltage to equal a target voltage level. The first rate may be the rate of charging an RC circuit including the output capacitance coupled to the output node.
    Type: Application
    Filed: May 31, 2022
    Publication date: November 30, 2023
    Inventors: Srikanth Govindarajulu, Hatem M. Osman, Michael D. Mulligan
  • Publication number: 20230387801
    Abstract: A method for operating a DC-DC converter includes generating an output voltage on an output node of the DC-DC converter based on an input voltage on an input node of the DC-DC converter using a transistor having a bulk terminal and a gate terminal, the output voltage being greater than the input voltage. The method includes coupling the input node to the bulk terminal and the gate terminal in response to the output voltage being less than the input voltage. The method includes coupling the output node to the bulk terminal in response to the output voltage exceeding the input voltage or a predetermined threshold voltage.
    Type: Application
    Filed: May 31, 2022
    Publication date: November 30, 2023
    Inventors: Srikanth Govindarajulu, Michael D. Mulligan, Hatem M. Osman
  • Publication number: 20230170799
    Abstract: In one embodiment, a method includes: enabling a pulse pair circuit of an integrated circuit in response to determining that a receiver associated with the integrated circuit is active; identifying that at least one comparator of a multi-output DC-DC converter trips, the DC-DC converter having a plurality of comparators each to compare a regulated voltage output by the DC-DC converter to a corresponding reference voltage; and generating, in the pulse pair circuit, a control pulse pair according to the tripped output, and driving a driver circuit of the DC-DC converter using the control pulse pair.
    Type: Application
    Filed: November 30, 2021
    Publication date: June 1, 2023
    Inventors: Hatem Osman, Michael D. Mulligan, Mohamed Elkholy
  • Publication number: 20190326816
    Abstract: An apparatus includes a voltage converter to convert an input voltage to an output voltage. The voltage converter includes a first set of switches operated during a first switching phase. The voltage converter further includes a second set of switches operated during a second switching phase. The duration of the second switching phase is related to the duration of the first switching phase.
    Type: Application
    Filed: April 20, 2018
    Publication date: October 24, 2019
    Inventors: Jeffrey L. Sonntag, Michael D. Mulligan, Ion C. Tesu
  • Patent number: 10423174
    Abstract: A pulse frequency modulated (PFM) voltage converter autonomously switches between buck, buck-boost, and boost modes as a function of the input and output voltages. The voltage converter may also switch autonomously between buck mode and a low drop out (LDO) mode when configured in a system in which the battery voltage is known to always be higher than the output voltage.
    Type: Grant
    Filed: April 23, 2018
    Date of Patent: September 24, 2019
    Assignee: Silicon Laboratories Inc.
    Inventors: Jeffrey L. Sonntag, Dazhi Wei, Michael D. Mulligan, Zachary A. Kaufman, Joselyn Torres-Torres
  • Patent number: 10263523
    Abstract: A DC-DC converter with a programmable pulse time limit. A charge pulse begins when the output voltage reaches a minimum threshold and terminates in response to a discharge indication, in which charge current flows through an inductive element while the charge pulse is provided. The discharge indication is provided to initiate a discharge pulse when the charge current reaches a peak threshold, which terminates in response to a reset indication. Current is discharged from the inductive element during the discharge pulse. A zero crossing detector provides the reset indication when the discharge current reaches a minimum level. A programmable timing circuit limits a duration of either one or both of the charge pulse and the discharge pulse to prevent hangup or excessive output voltage ripple. The DC-DC converter may include a memory that stores a digital value used to program the programmed time duration of the programmable timing circuit.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: April 16, 2019
    Assignee: Silicon Laboratories Inc.
    Inventors: Jeffrey L. Sonntag, Joselyn Torres-Torres, Michael D. Mulligan
  • Patent number: 7932754
    Abstract: A system, apparatus and method is arranged to adaptively adjust drive signals for a gate controlled switch circuit such that the amount of gate swing automatically changes based on the load conditions. An adaptive gate charge modulation (GCM) technique can be utilized to dynamically adjust the drive signals so that a substantially constant voltage drop is perceived across to a gate controlled switch circuit. The voltage drop across the gate controlled switch circuit can be set to a reference level that is adjusted whenever a change in system conditions are detected. The gate charge can then be adaptively increased and decreased during operation, within maximum and minimum limits, to substantially match the voltage drop of the gate control switch circuit to the reference level.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: April 26, 2011
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Michael D. Mulligan
  • Patent number: 7898825
    Abstract: A current-mode controller comprises an inductance element, at least one semiconductor switch coupled to the inductance element, and a ramp compensator coupled to sense an indication of current through the inductance element and coupled to control the at least one semiconductor switch that senses current during on-time of the DC-DC converter, infers current during off-time of the DC-DC converter, and determines a slope compensation signal based on the sensed and inferred currents.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: March 1, 2011
    Assignee: Akros Silicon, Inc.
    Inventors: Michael D Mulligan, Philip John Crawley, John Camagna
  • Publication number: 20090237058
    Abstract: A current-mode controller comprises an inductance element, at least one semiconductor switch coupled to the inductance element, and a ramp compensator coupled to sense an indication of current through the inductance element and coupled to control the at least one semiconductor switch that senses current during on-time of the DC-DC converter, infers current during off-time of the DC-DC converter, and determines a slope compensation signal based on the sensed and inferred currents.
    Type: Application
    Filed: March 24, 2008
    Publication date: September 24, 2009
    Inventors: Michael D. Mulligan, Philip John Crawley, John Camagna