Patents by Inventor Steve X. Chi

Steve X. Chi 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: 9535438
    Abstract: A switching rectifier circuit includes a pulse width modulation controller, a voltage switching circuit, a pulse width modulation comparator, an error amplifier, a voltage reference, a high threshold voltage comparator and a low threshold voltage comparator. A varying output voltage of the voltage regulator is sampled and compared to a high threshold voltage reference and a low threshold voltage reference. When the sampled output voltage is equal to or greater than the high threshold voltage reference the output voltage is decreased. When the sampled output voltage is equal to or less than the low threshold voltage reference the output voltage is increased.
    Type: Grant
    Filed: July 10, 2014
    Date of Patent: January 3, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Patent number: 9240778
    Abstract: A system and method of providing an analog make before break circuit includes a first transistor coupled in series with a second transistor, the first transistor being configured for conducting a high portion of an input signal, the second transistor being configured for conducting a low portion of the input signal. A third transistor is configured to interrupt a connection between the input signal and a first transistor input node, the third transistor having a third transistor threshold voltage between of about 90 and about 110 percent of a second transistor threshold voltage. A fourth transistor is configured to interrupt a connection between the input signal and a second transistor input node, the fourth transistor having a fourth transistor threshold voltage of between about 90 and about 110 percent of a first transistor threshold voltage.
    Type: Grant
    Filed: April 16, 2014
    Date of Patent: January 19, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Publication number: 20160011611
    Abstract: A switching rectifier circuit includes a pulse width modulation controller, a voltage switching circuit, a pulse width modulation comparator, an error amplifier, a voltage reference, a high threshold voltage comparator and a low threshold voltage comparator. A varying output voltage of the voltage regulator is sampled and compared to a high threshold voltage reference and a low threshold voltage reference. When the sampled output voltage is equal to or greater than the high threshold voltage reference the output voltage is decreased. When the sampled output voltage is equal to or less than the low threshold voltage reference the output voltage is increased.
    Type: Application
    Filed: July 10, 2014
    Publication date: January 14, 2016
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Patent number: 9203383
    Abstract: A soft-start generation system is configured to generate a soft-start voltage. The soft-start generation system includes sawtooth circuitry configured to generate current having a sawtooth waveform and staircase circuitry configured to generate current having an ascending staircase waveform. A ramp-up current may be generated that is a combination of the sawtooth current and the staircase current. The ramp-up current may continuously ramp up to a predetermined current level. The soft-start voltage may be generated based on the ramp-up current.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: December 1, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Publication number: 20150303911
    Abstract: A system and method of providing an analog make before break circuit includes a first transistor coupled in series with a second transistor, the first transistor being configured for conducting a high portion of an input signal, the second transistor being configured for conducting a low portion of the input signal. A third transistor is configured to interrupt a connection between the input signal and a first transistor input node, the third transistor having a third transistor threshold voltage between of about 90 and about 110 percent of a second transistor threshold voltage. A fourth transistor is configured to interrupt a connection between the input signal and a second transistor input node, the fourth transistor having a fourth transistor threshold voltage of between about 90 and about 110 percent of a first transistor threshold voltage.
    Type: Application
    Filed: April 16, 2014
    Publication date: October 22, 2015
    Applicant: SanDisk Technologies Inc.
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Publication number: 20140266110
    Abstract: An electronic circuit may output a slope compensation signal for performance of slope compensation of a current mode switching regulator. The circuit may generate a voltage across a storage device that is supplied to a voltage-to-current converter, which may generate a first current in response to the supplied voltage. Current mirror circuitry may mirror the current and supply the mirrored current to the storage device to generate the voltage. The current mirror circuitry may also mirror the current to generate a second mirrored current, which may be supplied to an output of the electronic circuit. In addition to using the first mirrored current to generate the voltage, the voltage may be generated by pulling down the voltage to ground in accordance with a duty cycle of a switching signal used for generation of an output of the current mode switching regulator.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Publication number: 20140266397
    Abstract: A soft-start generation system is configured to generate a soft-start voltage. The soft-start generation system includes sawtooth circuitry configured to generate current having a sawtooth waveform and staircase circuitry configured to generate current having an ascending staircase waveform. A ramp-up current may be generated that is a combination of the sawtooth current and the staircase current. The ramp-up current may continuously ramp up to a predetermined current level. The soft-start voltage may be generated based on the ramp-up current.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Inventors: Henry H. Yuan, Steve X. Chi, Ekram H. Bhuiyan
  • Patent number: 8716994
    Abstract: Techniques and circuits are described by which analog circuits may be quickly driven to desired states at startup in a fast and accurate manner.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: May 6, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Ekram H. Bhuiyan, Steve X. Chi
  • Patent number: 8624652
    Abstract: Delay circuits are described for which the delay remains substantially constant within a desired range of variation of supply voltage and/or temperature.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: January 7, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Ekram H. Bhuiyan, Steve X. Chi
  • Publication number: 20140002166
    Abstract: Delay circuits are described for which the delay remains substantially constant within a desired range of variation of supply voltage and/or temperature.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 2, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Ekram H. Bhuiyan, Steve X. Chi
  • Publication number: 20140002045
    Abstract: Techniques and circuits are described by which analog circuits may be quickly driven to desired states at startup in a fast and accurate manner.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 2, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Ekram H. Bhuiyan, Steve X. Chi
  • Patent number: 7875996
    Abstract: An electronic product includes an application specific semiconductor chip (ASIC) device which includes in its circuitry both a linear regulator module configured to be coupled to an optional external capacitance and a capless regulator module configured to be coupled to internal capacitance of the electronic product. Control logic of the ASIC device is responsive to a regulator selection signal for selecting one of the linear regulator module and the capless regulator module for use in powering the ASIC device. The control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: January 25, 2011
    Assignee: SanDisk Corporation
    Inventors: Daniel P. Nguyen, Steve X. Chi, Po-Shen Lai
  • Patent number: 7859134
    Abstract: A method for operating an electronic product having an application specific semiconductor circuit (ASIC) including in its circuitry both a linear regulator module for use with an optional external capacitance and a capless regulator module coupled to internal capacitance of the product selects a low-power sub-module or high-power sub-module of the capless regulator module for use in a power-up phase of the ASIC. Control logic of the ASIC determines if an external capacitance is present. If so, then the high-power capless sub-module is used during a power-up phase of the ASIC; if not only the low-power capless sub-module is used during the power-up phase of the ASIC. After power-up of the ASIC, the control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation or it may select one or the other for all times of post-power-up operation.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: December 28, 2010
    Assignee: SanDisk Corporation
    Inventors: Steve X. Chi, Yongliang Wang, Ekram Hossain Bhuiyan, Daniel P. Nguyen, Vincent Anthony Condito, Po-Shen Lai
  • Patent number: 7830039
    Abstract: Methods and systems for automatically and/or locally adjusting power-valid detection. In one class of embodiments, local power-on-reset circuits are included in individual power islands; in another class of embodiments, the power-on-reset circuit is automatically reprogrammed, depending on the detected interface voltage level, to use the same circuitry for power-valid detection in either case.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: November 9, 2010
    Assignee: SanDisk Corporation
    Inventors: Daniel P. Nguyen, Steve X. Chi
  • Publication number: 20090167093
    Abstract: Methods and systems for automatically and/or locally adjusting power-valid detection. In one class of embodiments, local power-on-reset circuits are included in individual power islands; in another class of embodiments, the power-on-reset circuit is automatically reprogrammed, depending on the detected interface voltage level, to use the same circuitry for power-valid detection in either case.
    Type: Application
    Filed: December 28, 2007
    Publication date: July 2, 2009
    Applicant: SanDisk Corporation
    Inventors: Daniel P. Nguyen, Steve X. Chi
  • Publication number: 20090160423
    Abstract: An electronic product includes an application specific semiconductor circuit (ASIC) including in its circuitry both a linear regulator module for use with an optional external capacitance and a capless regulator module coupled to internal capacitance of the product. The capless regulator module includes both a low-power sub-module and a high-power sub-module. Control logic of the ASIC is configured to determine if an external capacitance is present. If so, the control logic causes the high-power capless regulator sub-module to be used during a power-up phase of the ASIC; if not, only the low-power capless regulator sub-module is used during the power-up phase of the ASIC. After power-up of the ASIC, the control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation or it may select one or the other for all times of post-power-up operation.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventors: Steve X. Chi, Yongliang Wang, Ekram Hossain Bhuiyan, Daniel P. Nguyen, Vincent Anthony Condito, Po-Shen Lai
  • Publication number: 20090160421
    Abstract: An electronic product includes an application specific semiconductor chip (ASIC) device which includes in its circuitry both a linear regulator module configured to be coupled to an optional external capacitance and a capless regulator module configured to be coupled to internal capacitance of the electronic product. Control logic of the ASIC device is responsive to a regulator selection signal for selecting one of the linear regulator module and the capless regulator module for use in powering the ASIC device. The control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventors: Daniel P. Nguyen, Steve X. Chi, Po-Shen Lai
  • Publication number: 20090164807
    Abstract: A method for operating an electronic product having an application specific semiconductor circuit (ASIC) including in its circuitry both a linear regulator module for use with an optional external capacitance and a capless regulator module coupled to internal capacitance of the product selects a low-power sub-module or high-power sub-module of the capless regulator module for use in a power-up phase of the ASIC. Control logic of the ASIC determines if an external capacitance is present. If so, then the high-power capless sub-module is used during a power-up phase of the ASIC; if not only the low-power capless sub-module is used during the power-up phase of the ASIC. After power-up of the ASIC, the control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation or it may select one or the other for all times of post-power-up operation.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventors: Steve X. Chi, Yongliang Wang, Ekram Hossain Bhuiyan, Daniel P. Nguyen, Vincent Anthony Condito, Po-Shen Lai
  • Publication number: 20090160256
    Abstract: A method for operating an electronic product having an application specific semiconductor chip (ASIC) device which includes in its circuitry both a linear regulator module configured to be coupled to an optional external capacitance and a capless regulator module configured to be coupled to internal capacitance of the electronic product utilizes control logic of the ASIC device responsive to a regulator selection signal for selecting one of the linear regulator module and the capless regulator module for use in powering the ASIC device. The control logic may select the linear regulator module for certain times of operation and the capless regulator module for other times of operation.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventors: Daniel P. Nguyen, Steve X. Chi, Po-Shen Lai