Patents by Inventor Prasad Sawarkar

Prasad Sawarkar 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: 8922191
    Abstract: A peak current controlled switching voltage regulator system and method for providing a self-power down mode. An on-chip voltage regulator integrated into an on-chip digital logic circuit provides a core supply voltage to the on-chip digital logic circuit along with an off-chip inductor. An off-chip regulator connected to the on-chip digital logic circuit provides an external core supply voltage with respect to the on-chip digital logic circuit. A start-up circuit operates the on-chip voltage regulator in a self-power down mode for a pre-determined time period when the on-chip regulator is not connected to the off-chip inductor in order to maintain an equilibrium voltage supply with respect to the on-chip digital logic circuit.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: December 30, 2014
    Assignee: LSI Corporation
    Inventors: Prasad Sawarkar, Srinivas Reddy Chokka
  • Patent number: 8810231
    Abstract: A system and method for controlling ripple in an output voltage of a switching regulator is described. In one embodiment, the method includes providing a ramp circuit to selectively charge and discharge a ramp capacitor. The ramp capacitor provides a ramp voltage. The ramp voltage is selectively added to the output voltage to generate a summation voltage. The summation voltage is compared to a reference voltage to generate a control signal. An input voltage is coupled to an LC circuit based on the control signal. The LC circuit provides the output voltage. The input voltage is selectively coupled to the LC circuit when the ramp capacitor is selectively charged.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: August 19, 2014
    Assignee: LSI Corporation
    Inventors: Prasad Sawarkar, Srinivasa Reddy Chokka
  • Patent number: 8732511
    Abstract: An apparatus comprising a reference circuit, a resistor ladder, and an output circuit. The reference circuit may be configured to generate a reference signal in response to (i) a clock signal, (ii) a first phase signal and (iii) a second phase signal. The resistor ladder circuit may be configured to generate a tap voltage in response to the reference signal. The tap voltage may be generated by enabling one or more of a plurality of tap resistors. The output circuit may be configured to generate an adjusted clock signal in response to (i) the tap voltage, (ii) the clock signal, (iii) the first phase signal, (iv) the second phase signal, and (v) a reset signal. The adjusted clock signal may have an adjusted phase with respect to the clock signal.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: May 20, 2014
    Assignee: LSI Corporation
    Inventor: Prasad Sawarkar
  • Patent number: 8638136
    Abstract: A switching voltage regulator system and method for providing a start-up mode. An on-chip voltage regulator can be integrated with an on-chip digital logic circuit to provide a core supply voltage to the on-chip digital logic circuit along with an off-chip inductor and capacitor. A clock less start-up circuit automatically operates the on-chip voltage regulator in a start-up mode in order to maintain an equilibrium voltage supply with respect to the on-chip digital logic circuit. Such clock less start-up circuit provides soft start-up operation with respect to the on-chip voltage regulator without a clock signal.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: January 28, 2014
    Assignee: LSI Corporation
    Inventors: Prasad Sawarkar, Srinivas Reddy Chokka
  • Patent number: 8416011
    Abstract: A circuit includes a PMOS body bias circuit including a PMOS charge pump for generating a positive supply voltage, a PMOS reference voltage generator for providing a PMOS reference voltage, and a PMOS linear voltage regulator circuit for generating a PMOS body bias voltage upon receiving the positive supply voltage and the PMOS reference voltage. The circuit also includes a NMOS body bias circuit including a NMOS charge pump for generating a negative supply voltage, a NMOS reference voltage generator for providing a NMOS reference voltage, and a NMOS linear voltage regulator circuit for generating a NMOS body bias voltage upon receiving the negative supply voltage and the NMOS reference voltage. The PMOS body bias voltage and the NMOS body bias voltage drive bulk of PMOS and NMOS devices in the integrated circuit.
    Type: Grant
    Filed: November 8, 2010
    Date of Patent: April 9, 2013
    Assignee: LSI Corporation
    Inventors: Srinivas Reddy Chokka, Prasad Sawarkar
  • Publication number: 20130082752
    Abstract: An apparatus comprising a reference circuit, a resistor ladder, and an output circuit. The reference circuit may be configured to generate a reference signal in response to (i) a clock signal, (ii) a first phase signal and (iii) a second phase signal. The resistor ladder circuit may be configured to generate a tap voltage in response to the reference signal. The tap voltage may be generated by enabling one or more of a plurality of tap resistors. The output circuit may be configured to generate an adjusted clock signal in response to (i) the tap voltage, (ii) the clock signal, (iii) the first phase signal, (iv) the second phase signal, and (v) a reset signal. The adjusted clock signal may have an adjusted phase with respect to the clock signal.
    Type: Application
    Filed: September 29, 2011
    Publication date: April 4, 2013
    Inventor: Prasad Sawarkar
  • Publication number: 20130038311
    Abstract: A system and method for controlling ripple in an output voltage of a switching regulator is described. In one embodiment, the method includes providing a ramp circuit to selectively charge and discharge a ramp capacitor. The ramp capacitor provides a ramp voltage. The ramp voltage is selectively added to the output voltage to generate a summation voltage. The summation voltage is compared to a reference voltage to generate a control signal. An input voltage is coupled to an LC circuit based on the control signal. The LC circuit provides the output voltage. The input voltage is selectively coupled to the LC circuit when the ramp capacitor is selectively charged.
    Type: Application
    Filed: August 9, 2011
    Publication date: February 14, 2013
    Inventors: PRASAD SAWARKAR, SRINIVASA REDDY CHOKKA
  • Publication number: 20120161825
    Abstract: A switching voltage regulator system and method for providing a start-up mode. An on-chip voltage regulator can be integrated with an on-chip digital logic circuit to provide a core supply voltage to the on-chip digital logic circuit along with an off-chip inductor and capacitor. A clock less start-up circuit automatically operates the on-chip voltage regulator in a start-up mode in order to maintain an equilibrium voltage supply with respect to the on-chip digital logic circuit. Such clock less start-up circuit provides soft start-up operation with respect to the on-chip voltage regulator without a clock signal.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Inventors: Prasad Sawarkar, Srinivas Reddy Chokka
  • Publication number: 20120161735
    Abstract: A peak current controlled switching voltage regulator system and method for providing a self-power down mode. An on-chip voltage regulator integrated into an on-chip digital logic circuit provides a core supply voltage to the on-chip digital logic circuit along with an off-chip inductor. An off-chip regulator connected to the on-chip digital logic circuit provides an external core supply voltage with respect to the on-chip digital logic circuit. A start-up circuit operates the on-chip voltage regulator in a self-power down mode for a predetermined time period when the on-chip regulator is not connected to the off-chip inductor in order to maintain an equilibrium voltage supply with respect to the on-chip digital logic circuit.
    Type: Application
    Filed: June 23, 2011
    Publication date: June 28, 2012
    Inventors: Prasad Sawarkar, Srinivas Reddy Chokka
  • Publication number: 20120112820
    Abstract: A circuit and method for generating body bias voltage for an integrated circuit is disclosed. The circuit includes a PMOS body bias circuit including a PMOS charge pump for generating a positive supply voltage, a PMOS reference voltage generator for providing a PMOS reference voltage, and a PMOS linear voltage regulator circuit for generating a PMOS body bias voltage upon receiving the positive supply voltage and the PMOS reference voltage. The circuit also includes a NMOS body bias circuit including a NMOS charge pump for generating a negative supply voltage, a NMOS reference voltage generator for providing a NMOS reference voltage, and a NMOS linear voltage regulator circuit for generating a NMOS body bias voltage upon receiving the negative supply voltage and the NMOS reference voltage. The PMOS body bias voltage and the NMOS body bias voltage drive bulk of PMOS and NMOS devices in the integrated circuit.
    Type: Application
    Filed: November 8, 2010
    Publication date: May 10, 2012
    Inventors: SRINIVAS REDDY CHOKKA, Prasad Sawarkar