Patents by Inventor Dong-Jin Keum

Dong-Jin Keum 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: 9543829
    Abstract: Provided are a switching regulator and a comparator-based zero current detection method. The switching regulator comprises: a switch configured to connect to a switching node and control an inductor current flowing through the switching node; and a switch controller configured to control a turn-off time of the switch by detecting a change in a voltage of the switching node after the switch is turned off, wherein the switch controller comprises: a comparator configured to compare a first voltage applied to a first input terminal connected to the switching node with a second voltage applied to a second input terminal connected to a first terminal of the switch; and a control logic configured to receive a comparison signal of the comparator and control an offset of the comparator to adjust the turn-off time of the switch.
    Type: Grant
    Filed: January 3, 2014
    Date of Patent: January 10, 2017
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Min-ho Choi, Dong-Jin Keum
  • Patent number: 9438109
    Abstract: A bi-directional voltage positioning circuit includes a voltage to current converter, a current mirror circuit and a switch. The voltage to current converter converts a sensing voltage to a first current, and the sensing voltage is sensed based on a current flowing through an output coil connected between a switching node and an output node. The current mirror circuit mirrors the first current to generate a second current and a third current, the second current is N times greater than the first current, the third current is M times greater than the first current, and N and M are real numbers greater than zero. The switch provides a feedback node with one of the second current and third current in response to a switching control signal, and an output voltage of the output node is divided at the feedback node.
    Type: Grant
    Filed: February 24, 2014
    Date of Patent: September 6, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Sung-Woo Moon, Myeong-Lyong Ko, Yu-Seok Ko, Dong-Jin Keum, Hyun-Wook Yoo, Hwa-Yeal Yu
  • Publication number: 20160099640
    Abstract: A buck-boost converter includes: a converting circuit; a ripple injector; a hysteresis comparator; and a switching controller. The converting circuit is configured to generate an output voltage by adjusting an input voltage in a buck mode, a boost mode, and a buck-boost mode. The ripple injector is configured to generate a ripple based on switching signals corresponding to switching operations of the converting circuit. The hysteresis comparator outputs at least one switching control signal by comparing an output control voltage with a feedback voltage generated by adding the ripple to a divided voltage generated by performing a voltage division on the output voltage. The switching controller is configured to change a current flow path of the converting circuit based on the at least one switching control signal.
    Type: Application
    Filed: June 17, 2015
    Publication date: April 7, 2016
    Inventors: Min-Soo CHO, Jae-Yeol HAN, Dong-Jin KEUM, Il-Young SOHN, Ryotaro KUDO
  • Publication number: 20160036327
    Abstract: A buck converter using a variable pulse includes a switching unit configured to convert a supply voltage supplied from an external device into an internal voltage, and a pulse controller configured to variably control a driving time of the switching unit according to a result obtained by detecting a difference between the supply voltage and an output voltage which is the internal voltage.
    Type: Application
    Filed: February 6, 2015
    Publication date: February 4, 2016
    Inventors: Hyun-Seok Nam, Dong-Jin Keum, Yus Ko
  • Publication number: 20150357916
    Abstract: A method of operating a buck-boost converter including an inductor and a capacitor includes; operating the buck-boost converter in boost mode until a level of an input voltage applied at an input node of the buck-boost converter reaches a desired level of an output voltage apparent at an output node of the buck-boost converter, and after the level of an input voltage reaches the desired level of the output voltage, operating the buck-boost converter in buck mode, wherein operating the buck-boost converter in buck mode and operating the buck-boost converter in boost mode overlap at least in part temporally proximate a point at which the level of the input voltage exceeds the level of the output voltage.
    Type: Application
    Filed: April 16, 2015
    Publication date: December 10, 2015
    Inventors: GIL-WON YOON, DONG-JIN KEUM, YUS KO, GWANG-YOL NOH, SUNG-WOO MOON, MIN-HO CHOI
  • Patent number: 9148052
    Abstract: The switching regulator includes a voltage-to-current converter to convert a noise voltage into a noise current and output the noise current; and a sawtooth generator to output a sawtooth voltage signal having a frequency that varies in response to the noise current output from the voltage-to-current converter.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: September 29, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yus Ko, Dong Jin Keum
  • Publication number: 20150263615
    Abstract: A switching regulator includes a DC-DC converter and a dynamic voltage positioning circuit. The DC-DC converter includes an inductor connected between an input port and an output port. The dynamic voltage positioning circuit includes a sensing circuit and a mirroring circuit. The sensing circuit is configured to sense an inductor current flowing through the inductor, and to convert a voltage applied to a direct current resistance (DCR) of the inductor into a droop current using a variable resistor. The mirroring circuit is configured to cause a voltage drop at the output port of the DC-DC converter based on a current corresponding to a difference between a bias current and the droop current.
    Type: Application
    Filed: November 17, 2014
    Publication date: September 17, 2015
    Inventors: Sung-Woo MOON, Hyun-Wook YOO, Yus KO, Dong-Jin KEUM, Pyung-Woo YEON
  • Publication number: 20150180338
    Abstract: A switching regulator includes a power converting unit and a switch driving unit. The power converting unit is configured to generate a direct current (DC) output voltage based on a switch driving signal and a DC input voltage. The switch driving unit is configured to generate a ripple voltage having information of an inductor current flowing through the power converting unit, add the ripple voltage to a reference voltage to generate a first voltage having a ripple, generate a feedback voltage based on the DC output voltage, compare the first voltage with the feedback voltage in a hysteresis mode to generate a comparison output, and generate the switch driving signal based on the comparison output.
    Type: Application
    Filed: August 29, 2014
    Publication date: June 25, 2015
    Inventors: Min-Ho Choi, Dong-Jin Keum, Gil-Won Yoon, Yus Ko
  • Publication number: 20140253073
    Abstract: A bi-directional voltage positioning circuit includes a voltage to current converter, a current mirror circuit and a switch. The voltage to current converter converts a sensing voltage to a first current, and the sensing voltage is sensed based on a current flowing through an output coil connected between a switching node and an output node. The current mirror circuit mirrors the first current to generate a second current and a third current, the second current is N times greater than the first current, the third current is M times greater than the first current, and N and M are real numbers greater than zero. The switch provides a feedback node with one of the second current and third current in response to a switching control signal, and an output voltage of the output node is divided at the feedback node.
    Type: Application
    Filed: February 24, 2014
    Publication date: September 11, 2014
    Inventors: Sung-Woo MOON, Myeong-Lyong KO, Yu-Seok KO, Dong-Jin KEUM, Hyun-Wook YOO, Hwa-Yeal YU
  • Publication number: 20140191744
    Abstract: Provided are a switching regulator and a comparator-based zero current detection method. The switching regulator comprises: a switch configured to connect to a switching node and control an inductor current flowing through the switching node; and a switch controller configured to control a turn-off time of the switch by detecting a change in a voltage of the switching node after the switch is turned off, wherein the switch controller comprises: a comparator configured to compare a first voltage applied to a first input terminal connected to the switching node with a second voltage applied to a second input terminal connected to a first terminal of the switch; and a control logic configured to receive a comparison signal of the comparator and control an offset of the comparator to adjust the turn-off time of the switch.
    Type: Application
    Filed: January 3, 2014
    Publication date: July 10, 2014
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Min-ho CHOI, Dong-Jin KEUM
  • Patent number: 8710818
    Abstract: A power converter includes a power converting unit and a driving circuit. The power converting unit generates a DC output voltage based on a pull up driving signal, a pull down driving signal, and a DC input voltage. The driving circuit compensates for an inductor peak current, and performs in a pulse-frequency-modulation (PFM) mode and a pulse-width-modulation (PWM) mode to generate the pull-up driving signal and the pull-down driving signal based on the DC output voltage and the compensated inductor peak current. The power converter performs a mode transition between the PFM and PWM modes at a uniform load current, even when a magnitude of the DC output voltage varies.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: April 29, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-Hyuck Yu, Dong-Jin Keum
  • Patent number: 8624573
    Abstract: A power converter includes a zero-current detector having an adjustable offset voltage. The power converter includes a power converting unit and a switch driving circuit. The power converting unit generates a DC output voltage based on a pull-up driving signal, a pull-down driving signal and a DC input voltage. The switch driving circuit generates a first detection voltage signal based on the DC output voltage. The switch driving circuit includes a zero-current detector configured to adjust an offset voltage based on the first detection voltage signal and generate a zero-current detecting signal based on the offset voltage. The offset voltage and the zero-current detecting signal are associated with a current in the power converting unit. The switch driving circuit also includes a pulse-frequency modulating circuit configured to perform a pulse-frequency modulation (PFM) to generate the pull-up driving signal and the pull-down driving signal based on the zero-current detecting signal.
    Type: Grant
    Filed: May 26, 2011
    Date of Patent: January 7, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-Hyuck Yu, Dong-Jin Keum, Hyoung-Seok Oh
  • Publication number: 20120242313
    Abstract: The switching regulator includes a voltage-to-current converter to convert a noise voltage into a noise current and output the noise current; and a sawtooth generator to output a sawtooth voltage signal having a frequency that varies in response to the noise current output from the voltage-to-current converter.
    Type: Application
    Filed: March 22, 2012
    Publication date: September 27, 2012
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: YUS KO, DONG JIN KEUM
  • Patent number: 8126087
    Abstract: A DC offset correction circuit includes a DC offset detector generating a detection voltage based on a result of a comparison of a first reference voltage and a voltage difference between signals input to the DC offset detector, a comparator comparing a second reference voltage and the detection voltage and a third reference voltage and the detection voltage and outputting first and second comparison signals, respectively, as a result of the comparisons, and an up/down counter performing an up or a down count operation in response to one of the first or second comparison signals and, as a result of the up or down count operation, outputting a signal that causes at least one control signal for canceling a DC offset in a signal input to a receiver to be generated.
    Type: Grant
    Filed: January 15, 2009
    Date of Patent: February 28, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ju Young Han, Dong Jin Keum, Ji Soo Jang
  • Publication number: 20110309815
    Abstract: A power converter includes a power converting unit and a driving circuit. The power converting unit generates a DC output voltage based on a pull up driving signal, a pull down driving signal, and a DC input voltage. The driving circuit compensates for an inductor peak current, and performs in a pulse-frequency-modulation (PFM) mode and a pulse-width-modulation (PWM) mode to generate the pull-up driving signal and the pull-down driving signal based on the DC output voltage and the compensated inductor peak current. The power converter performs a mode transition between the PFM and PWM modes at a uniform load current, even when a magnitude of the DC output voltage varies.
    Type: Application
    Filed: June 16, 2011
    Publication date: December 22, 2011
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Jin-Hyuck Yu, Dong-Jin Keum
  • Publication number: 20110291632
    Abstract: A power converter includes a zero-current detector having an adjustable offset voltage. The power converter includes a power converting unit and a switch driving circuit. The power converting unit generates a DC output voltage based on a pull-up driving signal, a pull-down driving signal and a DC input voltage. The switch driving circuit generates a first detection voltage signal based on the DC output voltage. The switch driving circuit includes a zero-current detector configured to adjust an offset voltage based on the first detection voltage signal and generate a zero-current detecting signal based on the offset voltage. The offset voltage and the zero-current detecting signal are associated with a current in the power converting unit.
    Type: Application
    Filed: May 26, 2011
    Publication date: December 1, 2011
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Jin-Hyuck Yu, Dong-Jin Keum, Hyoung-Seok Oh
  • Patent number: 7755439
    Abstract: A PLL circuit for two point modulation includes a first loop filter, a second loop filter, a plurality of switching devices, and a calibration module. The first loop filter filters an output voltage of a charge pump during a gain calibration operation. The second loop filter filters the output voltage of the charge pump during a normal operation. The first loop filter has a bandwidth wider than that of the second loop filter to perform a fast calibration by reducing a lock time. The operation of the first loop filter, the operation of the second loop filter, and the opening of the first loop filter are determined by the switching operations of the switching devices. The calibration module adjusts a gain of analog modulation data based on a frequency error accumulated in the first loop filter after the first loop filter is open during the gain calibration operation.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: July 13, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hwa Yeal Yu, Dong Jin Keum
  • Publication number: 20090185639
    Abstract: A DC offset correction circuit includes a DC offset detector generating a detection voltage based on a result of a comparison of a first reference voltage and a voltage difference between signals input to the DC offset detector, a comparator comparing a second reference voltage and the detection voltage and a third reference voltage and the detection voltage and outputting first and second comparison signals, respectively, as a result of the comparisons, and an up/down counter performing an up or a down count operation in response to one of the first or second comparison signals and, as a result of the up or down count operation, outputting a signal that causes at least one control signal for canceling a DC offset in a signal input to a receiver to be generated.
    Type: Application
    Filed: January 15, 2009
    Publication date: July 23, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Ju Young Han, Dong Jin Keum, Ji Soo Jang
  • Publication number: 20090153254
    Abstract: A PLL circuit for two point modulation includes a first loop filter, a second loop filter, a plurality of switching devices, and a calibration module. The first loop filter filters an output voltage of a charge pump during a gain calibration operation. The second loop filter filters the output voltage of the charge pump during a normal operation. The first loop filter has a bandwidth wider than that of the second loop filter to perform a fast calibration by reducing a lock time. The operation of the first loop filter, the operation of the second loop filter, and the opening of the first loop filter are determined by the switching operations of the switching devices. The calibration module adjusts a gain of analog modulation data based on a frequency error accumulated in the first loop filter after the first loop filter is open during the gain calibration operation.
    Type: Application
    Filed: November 5, 2008
    Publication date: June 18, 2009
    Inventors: Hwa Yeal Yu, Dong Jin Keum
  • Patent number: 7362080
    Abstract: A power regulator includes a pass transistor, a feedback circuit, an error amplifier and a protection circuit. The pass transistor receives an unregulated first power supply voltage, and an output terminal of the power regulator outputs an output voltage varying depending upon a control signal. The feedback circuit senses a current flowing through the pass transistor and generates a feedback signal. The error amplifier compares a reference signal to the feedback signal and generates a control signal varying depending upon a voltage difference between the reference signal and the feedback signal. The protection circuit scales down a current flowing through the pass transistor by a prescribed ratio and changes a voltage of the control signal when the scaled-down current has a value higher than a prescribed value.
    Type: Grant
    Filed: August 20, 2005
    Date of Patent: April 22, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Il-Young Sohn, Dong-Jin Keum