Patents by Inventor Karthik Ramanan

Karthik Ramanan 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: 8008964
    Abstract: A device for providing a constant output voltage based on a variable input voltage is provided. The device may include: (1) a charge-pump comprising a plurality of cells, wherein each of the plurality of cells can be configured as an input cell, a stepping cell, or a load cell; (2) a comparator; and (3) a differentiator coupled to the comparator output, wherein the differentiator is configured to monitor the comparator output and produce a reset pulse each time the comparator output changes its state. The device may further include: (1) a decimator; (2) an up/down counter; and (3) a controller for detecting whether the device is operating in a first predetermined mode or a second predetermined mode, wherein the two modes relate to the configuration of the plurality of cells into the input cell, the stepping cell, and/or the load cell.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: August 30, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan
  • Patent number: 7965130
    Abstract: A charge pump and method for starting up a charge pump are provided. The charge pump comprises a plurality of charge pump cells and a start-up control circuit. Each charge pump cell has a clock terminal for receiving a delayed clock signal, an input terminal for receiving an input voltage, and an output terminal for providing a boosted voltage in response to receiving the clock signal and the input voltage. The start-up control circuit is coupled to the clock terminals of each of the plurality of charge pump cells. The start-up control circuit is for delaying the delayed clock signal provided to each charge pump cell of the plurality of charge pump cells. Each of the charge pump cells receives the delayed clock signal having a different predetermined delay so that each of the plurality of charge pump cells are enabled in a predetermined sequence during start-up of the charge pump.
    Type: Grant
    Filed: December 8, 2009
    Date of Patent: June 21, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan
  • Publication number: 20110133819
    Abstract: A charge pump and method for starting up a charge pump are provided. The charge pump comprises a plurality of charge pump cells and a start-up control circuit. Each charge pump cell has a clock terminal for receiving a delayed clock signal, an input terminal for receiving an input voltage, and an output terminal for providing a boosted voltage in response to receiving the clock signal and the input voltage. The start-up control circuit is coupled to the clock terminals of each of the plurality of charge pump cells. The start-up control circuit is for delaying the delayed clock signal provided to each charge pump cell of the plurality of charge pump cells. Each of the charge pump cells receives the delayed clock signal having a different predetermined delay so that each of the plurality of charge pump cells are enabled in a predetermined sequence during start-up of the charge pump.
    Type: Application
    Filed: December 8, 2009
    Publication date: June 9, 2011
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan
  • Patent number: 7948301
    Abstract: A charge pump charges a first capacitor to a predetermined input voltage using a first switch. The first switch is coupled to a first terminal of the first capacitor for coupling the first terminal to an input terminal that receives the predetermined input voltage. A second switch couples a second terminal of the first capacitor to a reference voltage terminal. Charge is sequentially transferred from the first capacitor to an output capacitance by using the first switch. A portion of charge is sequentially removed from the output capacitance to the input terminal using a third switch and a second capacitor. Configuration logic provides control signals to make one or more of a plurality of charge transfer capacitors switch the same as said first capacitor switches.
    Type: Grant
    Filed: August 28, 2009
    Date of Patent: May 24, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan
  • Publication number: 20110115549
    Abstract: A charge pump has circuitry and implements a method for monitoring a synchronous load by using a first voltage threshold below a target output voltage and a second voltage threshold above a target output voltage. An output terminal is coupled to the load. Charge is demanded by clocking the load. When the target output voltage passes below the first voltage threshold, a first value representing a present size of a charging capacitance is stored as a stored first value, and a second stored value representing a needed changed size of the charging capacitance is used. The present size of the charging capacitance is changed in response to the passing of the target output voltage below the first voltage threshold. When demand for charge from the load is reduced, a present value is saved and a prior value is restored to change the size of the charging capacitance.
    Type: Application
    Filed: November 16, 2009
    Publication date: May 19, 2011
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan
  • Publication number: 20110050326
    Abstract: A charge pump charges a first capacitor to a predetermined input voltage using a first switch. The first switch is coupled to a first terminal of the first capacitor for coupling the first terminal to an input terminal that receives the predetermined input voltage. A second switch couples a second terminal of the first capacitor to a reference voltage terminal. Charge is sequentially transferred from the first capacitor to an output capacitance by using the first switch. A portion of charge is sequentially removed from the output capacitance to the input terminal using a third switch and a second capacitor. Configuration logic provides control signals to make one or more of a plurality of charge transfer capacitors switch the same as said first capacitor switches.
    Type: Application
    Filed: August 28, 2009
    Publication date: March 3, 2011
    Inventors: Thomas D. Cook, Jeffrey C. Cunningham, Karthik Ramanan