Patents by Inventor Mehdi Rexha

Mehdi Rexha 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: 10564226
    Abstract: A diagnostic system for a DC-DC voltage converter having a high voltage switch, a low voltage switch, and a DC-DC voltage converter control circuit is provided. The system includes first and second tri-state buffer ICs and a microcontroller. The first tri-state buffer IC receives a first shutdown indicator voltage from the DC-DC voltage converter control circuit indicating that a first plurality of FET switches in a high side FET IC and a second plurality of FET switches in a low side FET IC have been transitioned to an open operational state. The first tri-state buffer IC outputs a second shutdown indicator voltage to the microcontroller that indicates that the first and second plurality of FET switches have been transitioned to the open operational state.
    Type: Grant
    Filed: November 10, 2017
    Date of Patent: February 18, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Chieh-Kai Chang
  • Patent number: 10511161
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. A first temperature sensor generates a first temperature signal associated with a buck mode integrated circuit. A first analog multiplexer outputs the first temperature signal to a first analog-to-digital converter which generates a first temperature value. A second temperature sensor generates a second temperature signal associated with a boost mode integrated circuit. A second analog multiplexer outputs the second temperature signal to a second analog-to-digital converter which generates a second temperature value. A microcontroller generates control signals to command first and second bi-directional switches in the DC-DC voltage converter to each transition to an open operational state if the first temperature value is greater than a first threshold temperature value.
    Type: Grant
    Filed: July 11, 2017
    Date of Patent: December 17, 2019
    Assignee: LG Chem, Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Kunal Tipnis, Chieh-Kai Chang, Su Hyuk Jang
  • Patent number: 10222429
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. The DC-DC voltage converter has a high voltage bi-directional MOSFET switch. The high voltage bi-directional MOSFET switch has a first node and a second node. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: March 5, 2019
    Assignee: LG Chem, Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Kunal Tipnis
  • Patent number: 10211736
    Abstract: A power supply system having a detection system for determining an unbalanced current condition and an over-current condition in a DC-DC voltage converter is provided. The detection system has a detection circuit that outputs a first diagnostic voltage indicating an unbalanced current condition between first and second switching banks in the DC-DC voltage converter based on a first voltage and an average voltage, or an over-current condition in the first switching bank based on the first voltage. The detection circuit outputs a second diagnostic voltage indicating the unbalanced current condition between the first and second switching banks in the DC-DC voltage converter based on a second voltage and the average voltage, or an over-current condition in the second switching bank based on the second voltage.
    Type: Grant
    Filed: January 23, 2017
    Date of Patent: February 19, 2019
    Assignee: LG Chem, Ltd.
    Inventors: Mehdi Rexha, Jaesam Lee, Chieh-Kai Chang
  • Publication number: 20180331621
    Abstract: A control system for controlling a DC-DC voltage converter circuit is provided. An output voltage controller outputs a DC-DC voltage converter control voltage to an input control terminal to increase a switching duty cycle within the DC-DC voltage converter circuit when the low voltage is less than an output reference voltage. An input voltage controller reduces the DC-DC voltage converter control voltage at the input control terminal of the DC-DC voltage converter circuit when a high voltage is less than an input reference voltage to reduce the switching duty cycle within the DC-DC voltage converter circuit.
    Type: Application
    Filed: January 25, 2018
    Publication date: November 15, 2018
    Inventors: Mehdi Rexha, Chieh-Kai Chang
  • Patent number: 10128648
    Abstract: A diagnostic system for a DC-DC voltage converter having a low voltage bi-directional MOSFET switch is provided. The low voltage bi-directional MOSFET switch has first and second nodes. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: November 13, 2018
    Assignee: LG Chem, Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha
  • Patent number: 10128751
    Abstract: A control system for controlling a DC-DC voltage converter circuit is provided. An output voltage controller outputs a DC-DC voltage converter control voltage to an input control terminal to increase a switching duty cycle within the DC-DC voltage converter circuit when the low voltage is less than an output reference voltage. An input voltage controller reduces the DC-DC voltage converter control voltage at the input control terminal of the DC-DC voltage converter circuit when a high voltage is less than an input reference voltage to reduce the switching duty cycle within the DC-DC voltage converter circuit.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: November 13, 2018
    Assignee: LG Chem, Ltd.
    Inventors: Mehdi Rexha, Chieh-Kai Chang
  • Publication number: 20180212522
    Abstract: A power supply system having a detection system for determining an unbalanced current condition and an over-current condition in a DC-DC voltage converter is provided. The detection system has a detection circuit that outputs a first diagnostic voltage indicating an unbalanced current condition between first and second switching banks in the DC-DC voltage converter based on a first voltage and an average voltage, or an over-current condition in the first switching bank based on the first voltage. The detection circuit outputs a second diagnostic voltage indicating the unbalanced current condition between the first and second switching banks in the DC-DC voltage converter based on a second voltage and the average voltage, or an over-current condition in the second switching bank based on the second voltage.
    Type: Application
    Filed: January 23, 2017
    Publication date: July 26, 2018
    Inventors: Mehdi Rexha, Jaesam Lee, Chieh-Kai Chang
  • Publication number: 20180149711
    Abstract: A diagnostic system for a DC-DC voltage converter having a high voltage switch, a low voltage switch, and a DC-DC voltage converter control circuit is provided. The system includes first and second tri-state buffer ICs and a microcontroller. The first tri-state buffer IC receives a first shutdown indicator voltage from the DC-DC voltage converter control circuit indicating that a first plurality of FET switches in a high side FET IC and a second plurality of FET switches in a low side FET IC have been transitioned to an open operational state. The first tri-state buffer IC outputs a second shutdown indicator voltage to the microcontroller that indicates that the first and second plurality of FET switches have been transitioned to the open operational state.
    Type: Application
    Filed: November 10, 2017
    Publication date: May 31, 2018
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Chieh-Kai Chang
  • Patent number: 9964599
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. The diagnostic system includes a first temperature sensor generating a first output voltage indicating a temperature level of a high voltage bi-directional MOSFET switch. The diagnostic system includes a microcontroller that samples the first output voltage at a first sampling rate utilizing a first channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first output voltage is greater than a first threshold voltage. The microcontroller sets a first temperature diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating the high voltage bi-directional MOSFET switch has an over-temperature condition.
    Type: Grant
    Filed: August 27, 2016
    Date of Patent: May 8, 2018
    Assignee: LG Chem, Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha
  • Publication number: 20180034263
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. A first temperature sensor generates a first temperature signal associated with a buck mode integrated circuit. A first analog multiplexer outputs the first temperature signal to a first analog-to-digital converter which generates a first temperature value. A second temperature sensor generates a second temperature signal associated with a boost mode integrated circuit. A second analog multiplexer outputs the second temperature signal to a second analog-to-digital converter which generates a second temperature value. A microcontroller generates control signals to command first and second bi-directional switches in the DC-DC voltage converter to each transition to an open operational state if the first temperature value is greater than a first threshold temperature value.
    Type: Application
    Filed: July 11, 2017
    Publication date: February 1, 2018
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Kunal Tipnis, Chieh-Kai Chang, Su Hyuk Jang
  • Publication number: 20170363691
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. The DC-DC voltage converter has a high voltage bi-directional MOSFET switch. The high voltage bi-directional MOSFET switch has a first node and a second node. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.
    Type: Application
    Filed: August 25, 2016
    Publication date: December 21, 2017
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Kunal Tipnis
  • Publication number: 20170363692
    Abstract: A diagnostic system for a DC-DC voltage converter is provided. The diagnostic system includes a first temperature sensor generating a first output voltage indicating a temperature level of a high voltage bi-directional MOSFET switch. The diagnostic system includes a microcontroller that samples the first output voltage at a first sampling rate utilizing a first channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first output voltage is greater than a first threshold voltage. The microcontroller sets a first temperature diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating the high voltage bi-directional MOSFET switch has an over-temperature condition.
    Type: Application
    Filed: August 27, 2016
    Publication date: December 21, 2017
    Inventors: Kerfegar K. Katrak, Mehdi Rexha
  • Publication number: 20170365996
    Abstract: A diagnostic system for a DC-DC voltage converter having a low voltage bi-directional MOSFET switch is provided. The low voltage bi-directional MOSFET switch has first and second nodes. The microcontroller samples a first voltage at the first node at a first sampling rate utilizing a first common channel in a first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first voltage is less than a first threshold voltage. The microcontroller sets a first voltage diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples indicating a voltage out of range low fault condition for the analog-to-digital converter.
    Type: Application
    Filed: August 25, 2016
    Publication date: December 21, 2017
    Inventors: Kerfegar K. Katrak, Mehdi Rexha
  • Patent number: 9784771
    Abstract: A diagnostic system for a power supply having first and second output terminals that output first and second reference voltages, respectively, is provided. The diagnostic system includes a microcontroller having an analog-to-digital converter with first and second banks of channels. The microcontroller samples the first reference voltage at a first sampling rate utilizing a first common channel in the first bank of channels to obtain a first predetermined number of voltage samples. The microcontroller determines a first number of voltage samples in the first predetermined number of voltage samples in which the first reference voltage was outside of a predetermined voltage range. The microcontroller sets a first power supply diagnostic flag equal to a first fault value if the first number of voltage samples is greater than a first threshold number of voltage samples.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: October 10, 2017
    Assignee: LG Chem Ltd.
    Inventors: Kerfegar K. Katrak, Mehdi Rexha, Kunal Tipnis