Patents by Inventor Jiwei Chen

Jiwei Chen 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: 10377639
    Abstract: The present invention relates to a method for directly synthesizing titanium dioxide from a titanium-rich organic phase prepared from ilmenite, and more particularly to a method in which a titanium-rich acidolysis solution is obtained by an efficient ore dissolving technology, titanium ions are transferred to the organic phase by means of an effective titanium extractant to obtain a high-purity and titanium-rich organic phase, and then the titanium dioxide is directly synthesized in the organic phase. With this method, the dissolution rate of ilmenite can be effectively improved, the process flow is shortened and production costs are reduced, and titanium dioxide with high yield and high quality is obtained.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: August 13, 2019
    Assignee: Fujian Kuncai Material Technology Co., Ltd.
    Inventors: Bingkun Xie, Zhicheng Cao, Jiwei Chen, Ming Fei
  • Patent number: 10374514
    Abstract: In one embodiment, a control circuit adjusts a duty cycle of a boost converter and comprises a duty cycle limiter generator configured to receive an input voltage provided to the boost converter and to generate a control signal to be provided to the boost converter for adjusting the duty cycle of the boost converter to control the output voltage of the booster converter in response to the input voltage. In one embodiment, the maximum duty cycle limit generator further generates the maximum duty cycle signal in response to an output voltage of the boost converter.
    Type: Grant
    Filed: November 5, 2014
    Date of Patent: August 6, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Subbarao Surendra Chakkirala, Jiwei Chen
  • Publication number: 20190084838
    Abstract: The present invention relates to a method for directly synthesizing titanium dioxide from a titanium-rich organic phase prepared from ilmenite, and more particularly to a method in which a titanium-rich acidolysis solution is obtained by an efficient ore dissolving technology, titanium ions are transferred to the organic phase by means of an effective titanium extractant to obtain a high-purity and titanium-rich organic phase, and then the titanium dioxide is directly synthesized in the organic phase. With this method, the dissolution rate of ilmenite can be effectively improved, the process flow is shortened and production costs are reduced, and titanium dioxide with high yield and high quality is obtained.
    Type: Application
    Filed: February 6, 2015
    Publication date: March 21, 2019
    Inventors: Bingkun XIE, Zhicheng CAO, Jiwei CHEN, Ming FEI
  • Patent number: 10059845
    Abstract: A preparation method of pearlescent pigment coating materials is provided. The method of the present invention lies in that titanium-iron ions in ilmenites are dissolved by using a hydrochloric acid at a certain temperature and pressure, and then ferrous chloride in the acidolysis solution is precipitated by adding hydrogen chloride gas, the remaining titanium-iron ions are separated from other colored ions by means of co-extraction using an extractant upon oxidation, and an enriched titanium oxydichloride solution and ferrous hydrous oxide are obtained by employing a fractional back extraction and enrichment method, the titanium oxydichloride solution can be used for mica-titanium based pearlescent pigment coating materials, and can also be used for preparing titanium dioxide; and the acidified ferrous hydrous oxide and the oxidized ferrous chloride can be used as iron based pearlescent pigment coating materials or used for preparing iron oxide pigments.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: August 28, 2018
    Assignee: Fujian Kuncai Material Technology Co., Ltd.
    Inventors: Bingkun Xie, Zhicheng Cao, Ming Fei, Jiwei Chen
  • Patent number: 9780657
    Abstract: The present disclosure pertains to circuits and methods for controlling a boost switching regulator based on inductor current. An input voltage is coupled to a first terminal of an inductor and the second terminal of the inductor is alternately coupled between a reference voltage and a boosted output voltage. The input voltage is further coupled to a first terminal of an integrator circuit, and a second terminal of the integrator circuit may be alternately coupled between the reference voltage and the boosted output voltage, for example, to produce a voltage corresponding to a current in the inductor. The present circuit may be used for voltage control or current control modes, or both, in a boost switching regulator.
    Type: Grant
    Filed: July 21, 2015
    Date of Patent: October 3, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Yikai Wang, Joseph Rutkowski, Jiwei Chen
  • Publication number: 20170275470
    Abstract: A preparation method of pearlescent pigment coating materials is provided. The method of the present invention lies in that titanium-iron ions in ilmenites are dissolved by using a hydrochloric acid at a certain temperature and pressure, and then ferrous chloride in the acidolysis solution is precipitated by adding hydrogen chloride gas, the remaining titanium-iron ions are separated from other colored ions by means of co-extraction using an extractant upon oxidation, and an enriched titanium oxydichloride solution and ferrous hydrous oxide are obtained by employing a fractional back extraction and enrichment method, the titanium oxydichloride solution can be used for mica-titanium based pearlescent pigment coating materials, and can also be used for preparing titanium dioxide; and the acidified ferrous hydrous oxide and the oxidized ferrous chloride can be used as iron based pearlescent pigment coating materials or used for preparing iron oxide pigments.
    Type: Application
    Filed: January 6, 2015
    Publication date: September 28, 2017
    Inventors: Bingkun Xie, Zhicheng CAO, Ming FEI, Jiwei CHEN
  • Patent number: 9755515
    Abstract: In one embodiment, a switching regulator includes an inductor, a first switch, and a second switch. The first and second switches generate current in the inductor. Inductor current may flow through the second switch with both a positive and negative polarity. Voltages on terminals of the second switch may be sensed, and an offset applied to generate a level shifted signal. In one embodiment, the switching regulator is a boost switching regulator, and the offset is generated using a current source. Matched MOS transistor switches may be used to couple voltages on terminals of the second switch to amplifier inputs, and the offset is introduced across an MOS switch coupled between one amplifier input and the output.
    Type: Grant
    Filed: August 4, 2015
    Date of Patent: September 5, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Joseph Rutkowski, Yikai Wang, Jiwei Chen
  • Patent number: 9729061
    Abstract: A boost regulator that selectively operates in an asynchronous mode, a synchronous mode, or an adaptive mode. In the adaptive mode, the boost mode regulator controls a high side switch according to an adaptive dead time. Adaptive mode allows the boost regulator to operate more efficiently than in asynchronous mode.
    Type: Grant
    Filed: July 8, 2015
    Date of Patent: August 8, 2017
    Assignee: QUALCOMM Incorporated
    Inventor: Jiwei Chen
  • Publication number: 20170040892
    Abstract: In one embodiment, a switching regulator includes an inductor, a first switch, and a second switch. The first and second switches generate current in the inductor. Inductor current may flow through the second switch with both a positive and negative polarity. Voltages on terminals of the second switch may be sensed, and an offset applied to generate a level shifted signal. In one embodiment, the switching regulator is a boost switching regulator, and the offset is generated using a current source. Matched MOS transistor switches may be used to couple voltages on terminals of the second switch to amplifier inputs, and the offset is introduced across an MOS switch coupled between one amplifier input and the output.
    Type: Application
    Filed: August 4, 2015
    Publication date: February 9, 2017
    Inventors: Joseph Rutkowski, Yikai Wang, Jiwei Chen
  • Publication number: 20170025947
    Abstract: The present disclosure pertains to circuits and methods for controlling a boost switching regulator based on inductor current. An input voltage is coupled to a first terminal of an inductor and the second terminal of the inductor is alternately coupled between a reference voltage and a boosted output voltage. The input voltage is further coupled to a first terminal of an integrator circuit, and a second terminal of the integrator circuit may be alternately coupled between the reference voltage and the boosted output voltage, for example, to produce a voltage corresponding to a current in the inductor. The present circuit may be used for voltage control or current control modes, or both, in a boost switching regulator.
    Type: Application
    Filed: July 21, 2015
    Publication date: January 26, 2017
    Inventors: Yikai Wang, Joseph Rutkowski, Jiwei Chen
  • Publication number: 20170012526
    Abstract: A boost regulator that selectively operates in an asynchronous mode, a synchronous mode, or an adaptive mode. In the adaptive mode, the boost mode regulator controls a high side switch according to an adaptive dead time. Adaptive mode allows the boost regulator to operate more efficiently than in asynchronous mode.
    Type: Application
    Filed: July 8, 2015
    Publication date: January 12, 2017
    Inventor: Jiwei Chen
  • Publication number: 20160126839
    Abstract: In one embodiment, a control circuit adjusts a duty cycle of a boost converter and comprises a duty cycle limiter generator configured to receive an input voltage provided to the boost converter and to generate a control signal to be provided to the boost converter for adjusting the duty cycle of the boost converter to control the output voltage of the booster converter in response to the input voltage. In one embodiment, the maximum duty cycle limit generator further generates the maximum duty cycle signal in response to an output voltage of the boost converter.
    Type: Application
    Filed: November 5, 2014
    Publication date: May 5, 2016
    Inventors: Subbarao Surendra Chakkirala, Jiwei Chen
  • Patent number: 7791469
    Abstract: A method and system for tracking a portable device. A tracking system includes a portable device, a first Radio Frequency (RF) module, and a second RF module. The first Radio Frequency (RF) module is installed in the portable device for transmitting a wireless signal. The second RF module is used for receiving the wireless signal. When a received amplitude of the wireless signal that is received by the second RF module is less than a predetermined value, the second RF module generates an alert.
    Type: Grant
    Filed: October 11, 2006
    Date of Patent: September 7, 2010
    Assignee: O2Micro International Limited
    Inventors: Jiwei Chen, James Lam
  • Patent number: 7769359
    Abstract: An adaptive wireless receiver and method thereof is disclosed in the present invention. The receiver includes an antenna, a bandpass filter, a front-end unit and a demodulator. Elements inside the front-end unit can be reused when the receiver operates in a zero intermediate frequency (ZIF) mode and in a low intermediate frequency (LIF) mode. The front-end unit includes a first and second down-conversion mixer, an analog filter, a first and second analog-to-digital converter (ADC), and a digital filter.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: August 3, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Dong Feng, Jiwei Chen
  • Patent number: 7615965
    Abstract: A method according to one embodiment may include selecting at least one power supply, among a plurality of different power supplies, and coupling at least one available power supply to a load. The method may also include selecting at least one charging mode, among a plurality of different charging modes, to charge a rechargeable battery. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: November 10, 2009
    Assignee: O2Micro International Limited
    Inventors: Vlad Mihail Popescu-Stanesti, Jiwei Chen, Oleg Kobildjanov
  • Patent number: 7508176
    Abstract: A controller for a DC to DC converter. The controller may comprise linear mode circuitry and switch mode control circuitry. The linear mode control circuitry may be capable of providing a first control signal to a controlled device of the DC to DC converter. The controlled device may operate as a variable resistor in response to the first control signal to control an output voltage of the DC to DC converter. The switch mode control circuitry may be capable of providing a second control signal to the controlled device of the DC to DC converter. The controlled device may turn ON and OFF in response to the second control signal to control the output voltage of the DC to DC converter. One of the linear mode control circuitry and the switch mode control circuitry may be enabled. The controller may also include protection circuitry.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: March 24, 2009
    Assignee: O2Micro International Limited
    Inventors: Alexandru Hartular, Chun Lu, You-Yuh Shyr, Constantin Bucur, Vlad Mihail Popescu-Stanesti, Jiwei Chen, Oleg Kobildjanov
  • Publication number: 20070287402
    Abstract: An adaptive wireless receiver and method thereof is disclosed in the present invention. The receiver includes an antenna, a bandpass filter, a front-end unit and a demodulator. Elements inside the front-end unit can be reused when the receiver operates in a zero intermediate frequency (ZIF) mode and in a low intermediate frequency (LIF) mode. The front-end unit includes a first and second down-conversion mixer, an analog filter, a first and second analog-to-digital converter (ADC), and a digital filter.
    Type: Application
    Filed: May 23, 2007
    Publication date: December 13, 2007
    Inventors: Dong Feng, Jiwei Chen
  • Publication number: 20070080824
    Abstract: A method and system for tracking a portable device. A tracking system includes a portable device, a first Radio Frequency (RF) module, and a second RF module. The first Radio Frequency (RF) module is installed in the portable device for transmitting a wireless signal. The second RF module is used for receiving the wireless signal. When a received amplitude of the wireless signal that is received by the second RF module is less than a predetermined value, the second RF module generates an alert.
    Type: Application
    Filed: October 11, 2006
    Publication date: April 12, 2007
    Inventors: Jiwei Chen, James Lam
  • Patent number: 7196592
    Abstract: A voltage-controlled oscillator circuit. A pair of inductors are coupled to a first power source. A pair of capacitors respectively coupled between a variable resistor and the pair of inductors in serial. A pair of first switches respectively coupled between the pair of capacitors and a second power source. The first switch of the pair has a first control gate coupled to a connection point of the other first switch and the corresponding capacitor.
    Type: Grant
    Filed: October 7, 2004
    Date of Patent: March 27, 2007
    Assignee: Winbond Electronics Corp.
    Inventors: Bingxue Shi, Jiwei Chen
  • Patent number: 7173402
    Abstract: A low dropout voltage regulator (LDO) includes a regulating circuit, an amplifier, and a first compensating path. The regulating circuit is configured to receive an input signal at an input terminal and provide an output signal at an output terminal in response to a control signal received at the control terminal. The amplifier may have a first input terminal coupled to a first input path and an output terminal be coupled to the control terminal of the regulating circuit via a path to provide the control signal. The first compensating path is coupled between a first node on the first input path and a first node on the path coupling the output terminal of the amplifier to the control terminal of the regulating circuit, the first compensating path including a first compensating capacitor.
    Type: Grant
    Filed: February 25, 2004
    Date of Patent: February 6, 2007
    Assignee: O2 Micro, Inc.
    Inventors: Jiwei Chen, Guoxing Li