Patents by Inventor Byungki Woo

Byungki Woo 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: 8339183
    Abstract: A charge pump circuit for generating an output voltage is described. Charge pump circuits typically have two branches. As the clocks supplying the branches of a charge pump circuit alternate, the output of each branch will alternately provide an output voltage, which are then combined to form the pump output. The techniques described here allow charge to be transferred between the two branches, so that as the capacitor of one branch discharges, it is used to charge up the capacitor in the other branch. An exemplary embodiment using a voltage doubler-type of circuit, with the charge transfer between the branches accomplished using a switch controller by a boosted version of the clock signal, which is provided by a one-sided voltage doubler.
    Type: Grant
    Filed: July 24, 2009
    Date of Patent: December 25, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Khin Htoo, Feng Pan, Byungki Woo, Trung Pham, Yuxin Wang
  • Patent number: 8054681
    Abstract: A non-volatile memory device has individual pages of memory cells to be sensed in parallel. The memory device includes a source level tracking circuit coupled to receive a predetermined word line voltage from a word line voltage supply and the voltage level at the aggregate source node of one or more pages and coupled to provide to word lines of the memory an output voltage during the sensing operation, where the source level tracking circuit includes an op amp whereby the output voltage is the word line voltage offset by an amount to track the voltage level at the aggregate node and compensate for source bias errors due to a finite resistance in the ground loop.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: November 8, 2011
    Assignee: SanDisk Technologies Inc.
    Inventors: Feng Pan, Trung Pham, Byungki Woo
  • Patent number: 7889575
    Abstract: Techniques and corresponding circuitry for deriving a supply a bias voltage for a memory cell array from a received reference voltage is presented. The circuit includes a voltage determination circuit, which is connected to receive the reference voltage and generate from it the bias voltage, a temperature sensing circuit, and a calibration circuit. The calibration circuit is connected to receive the bias voltage and to receive a temperature indication from the temperature sensing circuit and determine from the bias voltage and temperature indication a compensation factor that is supplied to the voltage determination circuit, which adjusts the bias voltage based upon the compensation factor.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: February 15, 2011
    Assignee: SanDisk Corporation
    Inventors: Yuxin Wang, Feng Pan, Byungki Woo, Trung Pham, Khin Htoo
  • Publication number: 20110018617
    Abstract: A charge pump circuit for generating an output voltage is described. Charge pump circuits typically have two branches. As the clocks supplying the branches of a charge pump circuit alternate, the output of each branch will alternately provide an output voltage, which are then combined to form the pump output. The techniques described here allow charge to be transferred between the two branches, so that as the capacitor of one branch discharges, it is used to charge up the capacitor in the other branch.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 27, 2011
    Inventors: Khin Htoo, Feng Pan, Byungki Woo, Trung Pham, Yuxin Wang
  • Publication number: 20100157681
    Abstract: A non-volatile memory device has individual pages of memory cells to be sensed in parallel. The memory device includes a source level tracking circuit coupled to receive a predetermined word line voltage from a word line voltage supply and the voltage level at the aggregate source node of one or more pages and coupled to provide to word lines of the memory an output voltage during the sensing operation, where the source level tracking circuit includes an op amp whereby the output voltage is the word line voltage offset by an amount to track the voltage level at the aggregate node and compensate for source bias errors due to a finite resistance in the ground loop.
    Type: Application
    Filed: March 2, 2010
    Publication date: June 24, 2010
    Inventors: Feng Pan, Trung Pham, Byungki Woo
  • Patent number: 7701761
    Abstract: A non-volatile memory device has individual pages of memory cells to be sensed in parallel. The memory device includes a source level tracking circuit coupled to receive a predetermined word line voltage from a word line voltage supply and the voltage level at the aggregate source node of one or more pages and coupled to provide to word lines of the memory an output voltage during the sensing operation, where the source level tracking circuit includes an op amp whereby the output voltage is the word line voltage offset by an amount to track the voltage level at the aggregate node and compensate for source bias errors due to a finite resistance in the ground loop.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: April 20, 2010
    Assignee: SanDisk Corporation
    Inventors: Feng Pan, Trung Pham, Byungki Woo
  • Publication number: 20100073069
    Abstract: Techniques and corresponding circuitry for deriving a supply a bias voltage for a memory cell array from a received reference voltage is presented. The circuit includes a voltage determination circuit, which is connected to receive the reference voltage and generate from it the bias voltage, a temperature sensing circuit, and a calibration circuit. The calibration circuit is connected to receive the bias voltage and to receive a temperature indication from the temperature sensing circuit and determine from the bias voltage and temperature indication a compensation factor that is supplied to the voltage determination circuit, which adjusts the bias voltage based upon the compensation factor.
    Type: Application
    Filed: September 22, 2008
    Publication date: March 25, 2010
    Inventors: Yuxin Wang, Feng Pan, Byungki Woo, Trung Pham, Khin Htoo
  • Publication number: 20090161434
    Abstract: A non-volatile memory device has individual pages of memory cells to be sensed in parallel. The memory device includes a source level tracking circuit coupled to receive a predetermined word line voltage from a word line voltage supply and the voltage level at the aggregate source node of one or more pages and coupled to provide to word lines of the memory an output voltage during the sensing operation, where the source level tracking circuit includes an op amp whereby the output voltage is the word line voltage offset by an amount to track the voltage level at the aggregate node and compensate for source bias errors due to a finite resistance in the ground loop.
    Type: Application
    Filed: December 20, 2007
    Publication date: June 25, 2009
    Inventors: Feng Pan, Trung Pham, Byungki Woo