Patents by Inventor Sameer Wadhwa

Sameer Wadhwa 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: 7948330
    Abstract: An integrated circuit incorporating a bias circuit for a current-controlled oscillator (ICO) with improved power supply rejection ratio (PSRR) is described. The bias circuit for the ICO includes two error amplifiers. The first error amplifier regulates the bias voltage, VBN, referenced to a ground supply (GND). The second error amplifier regulates the bias voltage, VBP, referenced to a positive power supply (VDD). The VBP and VBN bias voltages have improved PSRR relative to conventional ICO bias circuits for noise injected into VDD and GND.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: May 24, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Dongwon Seo, Sameer Wadhwa
  • Publication number: 20110090940
    Abstract: Closed-loop techniques for adjusting the duty cycle of a cyclical signal, e.g., a clock signal, to approach a target value. In an exemplary embodiment, a charge pump is coupled to a charge and sample module, which drives a de-skew circuit in a negative feedback loop. The charge and sample module couples the charge pump to the integration capacitor during two of four successive phases, and also couples the integration capacitor to sampling capacitors during the other two of the four successive phases. The voltages across the sampling capacitors may be used to control the de-skew circuit, which adjusts the duty cycle of a cyclical signal to be adjusted.
    Type: Application
    Filed: October 21, 2009
    Publication date: April 21, 2011
    Applicant: QUALCOMM Incorporated
    Inventors: Sameer Wadhwa, Marzio Pedrali-Noy
  • Publication number: 20100237952
    Abstract: An integrated circuit incorporating a bias circuit for a current-controlled oscillator (ICO) with improved power supply rejection ratio (PSRR) is described. The bias circuit for the ICO includes two error amplifiers. The first error amplifier regulates the bias voltage, VBN, referenced to a ground supply (GND). The second error amplifier regulates the bias voltage, VBP, referenced to a positive power supply (VDD). The VBP and VBN bias voltages have improved PSRR relative to conventional ICO bias circuits for noise injected into VDD and GND.
    Type: Application
    Filed: March 19, 2009
    Publication date: September 23, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Dongwon Seo, Sameer Wadhwa
  • Publication number: 20100141223
    Abstract: A low drop-out (LDO) voltage regulator with a wide bandwidth power supply rejection ratio (PSRR) is described. In one aspect, the LDO voltage regulator includes two individual voltage regulator circuit stages. A first stage voltage regulator circuit output is at an intermediate voltage (VINT) between an input supply voltage (VDD) and a final regulated output voltage (VREG). A second stage voltage regulator circuit output is at the final regulated output voltage (VREG) and is optimized for noise-sensitive analog circuits across a wide operating bandwidth. The first stage voltage regulator circuit has a zero frequency while the second stage voltage regulator circuit has a matching pole frequency to minimize the AC response from VDD to VREG across all frequencies.
    Type: Application
    Filed: December 9, 2008
    Publication date: June 10, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventor: Sameer Wadhwa
  • Patent number: 7635994
    Abstract: Method and apparatus are provided for fast rail-to-rail voltage comparison. A rail-to-rail voltage comparator for indicating one of two states with an output signal in response to an input signal is provided comprising an input stage having an input configured to receive the input signal and having an output, and an amplification circuit having an input coupled to the output of the input stage. The input stage comprises a first differential amplifier having a first input-voltage range and configured to produce a first current based on the input signal, a second differential amplifier having a second input-voltage range and configured to produce a second current based on the input signal, and a summing circuit having a first input coupled to the first differential amplifier and having a second input coupled to the second differential amplifier. The first input-voltage range overlaps the second input-voltage range.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: December 22, 2009
    Assignee: Spansion LLC
    Inventor: Sameer Wadhwa
  • Publication number: 20090237040
    Abstract: Power efficient power supply regulator circuits are disclosed. The circuits are configured to modify their overhead current according to current load. This is particularly advantageous for use in display devices with widely varying current loads. Such displays include bi-stable displays, such as interferometric modulation displays, LCD displays, and DMD displays.
    Type: Application
    Filed: March 18, 2008
    Publication date: September 24, 2009
    Applicant: QUALCOMM MEMS Technologies, Inc.
    Inventor: Sameer Wadhwa
  • Patent number: 7498849
    Abstract: A sense amplifier includes a reference voltage generator for generating a reference output voltage and a core output voltage generator for generating a core output voltage. The core output voltage generator includes a core front-end stage and a core back-end stage or includes a plurality of amplifier transistors each conducting a portion of a core current through a current conducting device such as core cell. The sizes and/or connections of transistors of such components result in high voltage swing and thus high sensitivity of the sense amplifier.
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: March 3, 2009
    Assignee: Spansion LLC
    Inventors: Takao Akaogi, Sameer Wadhwa, Michael Achter, Bhimachar Venkatesh
  • Publication number: 20080192029
    Abstract: A display array which can reduce the row connections between the display and the driver circuit and methods of manufacturing and operating the same are disclosed. In one embodiment, a display device comprises an array of microelectromechanical system (MEMS) display elements and a plurality of passive impedance network circuits coupled to said array and configured to provide row output voltages to drive said array. Each passive impedance network comprises an output to a row of display elements and three or more inputs. No more than one input is shared by two passive impedance networks.
    Type: Application
    Filed: February 8, 2007
    Publication date: August 14, 2008
    Inventors: Michael Hugh Anderson, Franklin Antonio, Sameer Wadhwa
  • Patent number: 7397696
    Abstract: The present invention pertains to a circuit arrangement that, in one example, facilitates reading or determining an amount of current that flows through a memory cell when one or more voltages are applied to the cell. The amount of current resulting from the applied voltages is a function of the amount of charge stored within the cell, among other things, and the amount of stored charge represents information stored within the cell. As such, reading the resulting current allows data stored within the cell to be accessed and retrieved. It will be appreciated however, that use of the circuitry disclosed herein is not limited to memory applications. Rather, it can be used in any application where current sensing is required along with a regulated supply voltage.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: July 8, 2008
    Assignee: Spansion LLC
    Inventors: Sameer Wadhwa, Michael Achter, Bhimachar Venkatesh
  • Publication number: 20080068046
    Abstract: A sense amplifier includes a reference voltage generator for generating a reference output voltage and a core output voltage generator for generating a core output voltage. The core output voltage generator includes a core front-end stage and a core back-end stage or includes a plurality of amplifier transistors each conducting a portion of a core current through a current conducting device such as core cell. The sizes and/or connections of transistors of such components result in high voltage swing and thus high sensitivity of the sense amplifier.
    Type: Application
    Filed: November 15, 2007
    Publication date: March 20, 2008
    Inventors: Takao Akaogi, Sameer Wadhwa, Michael Achter, Bhimachar Venkatesh
  • Patent number: 7327186
    Abstract: A circuit is disclosed that compensates for changes in temperature as well as for fluctuations in a supply voltage (Vcc) so that voltage reference values generated thereby are maintained at substantially constant levels irrespective of changes in temperature or fluctuations in supply voltage. The circuit is also configured to produce a wide range of voltage reference values so that it can independently service the needs of many different applications. Additionally, the circuit is designed using meal oxide semiconductor (MOS) technology, as opposed to more conventional bipolar technology, so that it “settles down” or generates reference values relatively quickly.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: February 5, 2008
    Assignee: Spansion LLC
    Inventors: Sameer Wadhwa, Bhimachar Venkatesh
  • Patent number: 7312641
    Abstract: A sense amplifier includes a reference voltage generator for generating a reference output voltage and a core output voltage generator for generating a core output voltage. The core output voltage generator includes a core front-end stage and a core back-end stage or includes a plurality of amplifier transistors each conducting a portion of a core current through a current conducting device such as core cell. The sizes and/or connections of transistors of such components result in high voltage swing and thus high sensitivity of the sense amplifier.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: December 25, 2007
    Assignee: Spansion LLC
    Inventors: Takao Akaogi, Sameer Wadhwa, Michael Achter, Bhimachar Venkatesh
  • Patent number: 7099204
    Abstract: The present invention facilitates more accurate data reads by compensating for parasitic behavior—thus regulating the voltage at the drain of a core memory cell rather than at the output of a sensing circuit. More particularly, respective voltages at one or more nodes, such as the start of a bitline at a sensing circuit, for example, are adjusted to compensate for voltage drops that may occur due to parasitic behavior. Maintaining the substantially constant voltage levels at core memory cells allows comparisons to be made under ideal conditions while reducing the side leakages in virtual ground schemes. This mitigates margin loss and facilitates more reliable data sensing.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: August 29, 2006
    Assignee: Spansion LLC
    Inventors: Sameer Wadhwa, Bhimachar Venkatesh
  • Publication number: 20060139062
    Abstract: A sense amplifier includes a reference voltage generator for generating a reference output voltage and a core output voltage generator for generating a core output voltage. The core output voltage generator includes a core front-end stage and a core back-end stage or includes a plurality of amplifier transistors each conducting a portion of a core current through a current conducting device such as core cell. The sizes and/or connections of transistors of such components result in high voltage swing and thus high sensitivity of the sense amplifier.
    Type: Application
    Filed: December 28, 2004
    Publication date: June 29, 2006
    Inventors: Takao Akaogi, Sameer Wadhwa, Michael Achter, Bhimachar Venkatesh