Patents by Inventor Kun LAN

Kun LAN 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: 12500590
    Abstract: A PLL circuit generates an output signal having an output frequency and includes a voltage-to-current conversion circuit, a frequency compensation circuit, and an ICO. The voltage-to-current conversion circuit is configured to generate a first control current according to a control voltage, wherein the control voltage is generated according to a reference signal and a feedback signal derived from the output signal. The frequency compensation circuit is configured to generate a second control current according to the control voltage. The ICO generates the output signal according to an oscillation current, wherein the oscillation current is a sum of the first control current and the second control current. In response to the frequency compensation circuit detecting that the control voltage is out of a predetermined range, the second control current is controlled to be negatively correlated with the output frequency.
    Type: Grant
    Filed: April 18, 2024
    Date of Patent: December 16, 2025
    Assignee: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Ming Wang, Kun Lan, Cong Liu
  • Publication number: 20250300662
    Abstract: A PLL circuit generates an output signal having an output frequency and includes a voltage-to-current conversion circuit, a frequency compensation circuit, and an ICO. The voltage-to-current conversion circuit is configured to generate a first control current according to a control voltage, wherein the control voltage is generated according to a reference signal and a feedback signal derived from the output signal. The frequency compensation circuit is configured to generate a second control current according to the control voltage. The ICO generates the output signal according to an oscillation current, wherein the oscillation current is a sum of the first control current and the second control current. In response to the frequency compensation circuit detecting that the control voltage is out of a predetermined range, the second control current is controlled to be negatively correlated with the output frequency.
    Type: Application
    Filed: April 18, 2024
    Publication date: September 25, 2025
    Inventors: Ming WANG, Kun LAN, Cong LIU
  • Patent number: 12143109
    Abstract: A device for correcting a duty cycle, comprising: a duty adjustor circuit, configured to receive an input clock signal and a tuning signal, to generate an output clock signal; a first charge pump, configured to charge a first capacitor for a predetermined time period to generate a first voltage; a second charge pump, configured to charge a second capacitor for a time period corresponding to the duty cycle of the output clock signal to generate a second voltage; a first sampling and hold circuit, configured to sample the first voltage to generate a first sampled voltage; a second sampling and hold circuit, configured to sample the second voltage to generate a second sampled voltage; and an error amplifier, configured to generate the tuning signal according to a difference value between the first sampled voltage and the second sampled voltage.
    Type: Grant
    Filed: June 6, 2023
    Date of Patent: November 12, 2024
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Ming Wang, Kun Lan, Cong Liu
  • Publication number: 20240356536
    Abstract: A device for correcting a duty cycle, comprising: a duty adjustor circuit, configured to receive an input clock signal and a tuning signal, to generate an output clock signal; a first charge pump, configured to charge a first capacitor for a predetermined time period to generate a first voltage; a second charge pump, configured to charge a second capacitor for a time period corresponding to the duty cycle of the output clock signal to generate a second voltage; a first sampling and hold circuit, configured to sample the first voltage to generate a first sampled voltage; a second sampling and hold circuit, configured to sample the second voltage to generate a second sampled voltage; and an error amplifier, configured to generate the tuning signal according to a difference value between the first sampled voltage and the second sampled voltage.
    Type: Application
    Filed: June 6, 2023
    Publication date: October 24, 2024
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Ming Wang, Kun Lan, Cong Liu
  • Patent number: 10348271
    Abstract: An impedance matching circuit and an interface circuit are provided. The impedance matching circuit includes a reference-voltage generation circuit, a control-signal generation circuit, and a circuit subunit. The reference-voltage generation circuit generates a reference voltage. The control-signal generation circuit generates a plurality of control signals. The circuit subunit is coupled to the reference-voltage generation circuit and the control-signal generation circuit. The circuit subunit receives the reference voltage and the control signals. The circuit subunit includes a plurality of transistors. The plurality of transistors are turned on or off according to levels of the control signals, and the plurality of transistors provide an impedance which matches the impedance of a receiver when the interface circuit is powered. The reference voltage is provided to bulks of the transistors, so that the voltages of the bulks of the transistors are not equal to zero volts.
    Type: Grant
    Filed: January 10, 2018
    Date of Patent: July 9, 2019
    Assignee: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Bo Hu, Kun Lan
  • Patent number: 10135442
    Abstract: A current-mode logic circuit is provided. The current-mode logic circuit includes a transmitter module. The transmitter module includes an output impedance circuit, a switch circuit, and a current source. The output impedance circuit provides an adjustable output resistor. The adjustable output resistor includes floating resistors and/or pull-up resistors. The switch circuit is coupled to the output impedance circuit. The switch circuit receives differential input signals, outputs differential output signals, and controls high-low level switching of the differential input signals and the differential output signals according to the adjustable output resistor. The current source is coupled to the output impedance circuit and the switch circuit. The current source provides currents to the output impedance circuit and the switch circuit.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: November 20, 2018
    Assignee: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Yiming Tang, Bo Hu, Kun Lan
  • Publication number: 20180254767
    Abstract: An impedance matching circuit and an interface circuit are provided. The impedance matching circuit includes a reference-voltage generation circuit, a control-signal generation circuit, and a circuit subunit. The reference-voltage generation circuit generates a reference voltage. The control-signal generation circuit generates a plurality of control signals. The circuit subunit is coupled to the reference-voltage generation circuit and the control-signal generation circuit. The circuit subunit receives the reference voltage and the control signals. The circuit subunit includes a plurality of transistors. The plurality of transistors are turned on or off according to levels of the control signals, and the plurality of transistors provide an impedance which matches the impedance of a receiver when the interface circuit is powered. The reference voltage is provided to bulks of the transistors, so that the voltages of the bulks of the transistors are not equal to zero volts.
    Type: Application
    Filed: January 10, 2018
    Publication date: September 6, 2018
    Inventors: Bo HU, Kun LAN
  • Publication number: 20180083624
    Abstract: A current-mode logic circuit is provided. The current-mode logic circuit includes a transmitter module. The transmitter module includes an output impedance circuit, a switch circuit, and a current source. The output impedance circuit provides an adjustable output resistor. The adjustable output resistor includes floating resistors and/or pull-up resistors. The switch circuit is coupled to the output impedance circuit. The switch circuit receives differential input signals, outputs differential output signals, and controls high-low level switching of the differential input signals and the differential output signals according to the adjustable output resistor. The current source is coupled to the output impedance circuit and the switch circuit. The current source provides currents to the output impedance circuit and the switch circuit.
    Type: Application
    Filed: September 19, 2017
    Publication date: March 22, 2018
    Inventors: Yiming TANG, Bo HU, Kun LAN
  • Publication number: 20180083628
    Abstract: A pre-driver circuit is provided. The pre-driver circuit includes a switch circuit, a common-mode voltage control circuit, and a current supply circuit. The switch circuit receives differential input signals, outputs differential output signals, and controls switching between a high level and a low level of the differential output signals and the differential input signals. The common-mode voltage control circuit is coupled to the switch circuit. The common-mode voltage control circuit receives a reference voltage and controls a common-mode voltage of the differential output signals according to the reference voltage. The current supply circuit is coupled to the switch circuit and the common-mode voltage control circuit. The current supply circuit provides a driving current for the switch circuit and the common-mode voltage control circuit.
    Type: Application
    Filed: September 18, 2017
    Publication date: March 22, 2018
    Inventors: Yiming TANG, Bo HU, Kun LAN
  • Patent number: 8922409
    Abstract: A switch-driving circuit and a Digital-to-Analog Converter (DAC) using the switch-driving circuit are provided. The switch-driving circuit includes a main cell and a reference cell. The main cell includes a current source and a resistance-control component electronically connected to the current source. The reference cell is coupled to the current source and the resistance-control component, and includes a first loop, the first loop is configured to track a target reference voltage so as to provide at least one first control voltage to control a resistance change of the resistance-control component. The reference cell and the main cell are implemented by MOS transistors in place of capacitors which occupy an increased circuit area, rendering reduced circuit area for the switch-driving circuit, and decreasing manufacturing costs. Further, the switch-driving circuit outputs a voltage signal with reduced noise, increasing the performance of the Digital-to-Analog Converter.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 30, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Cheng Tao, Yue Feng, Kun Lan, Yu-Kai Chou
  • Patent number: 8836556
    Abstract: An Analog to Digital Converter (ADC), an analog-to-digital conversion method, and an integrated circuit including the ADC. The ADC includes an input adjustment buffer stage, a sub-ADC, and a sample switch. The sample switch is coupled between the output node of the input adjustment buffer stage and the input node of the sub-ADC. When the sample switch is opened, the input adjustment buffer stage is configured to switch between a first work state and a second work state according to a predetermined rule, and to adjust an input voltage signal of the input adjustment buffer stage based on transitions between the first and second work states. When the sample switch is closed, the input adjustment buffer stage is configured to provide an adjusted voltage signal to the input node of the sub-ADC, and the sub-ADC is configured to perform an analog-to-digital conversion onto the adjusted voltage signal.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: September 16, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Yingyi Liu, Yu-Kai Chou, Kun Lan
  • Patent number: 8810218
    Abstract: A voltage regulator includes a pass transistor, an operational amplifier and a voltage divider circuit. The pass transistor receives a supply voltage to generate a regulated output voltage according to a control signal. The operational amplifier generates the control signal according to a feedback voltage. The voltage divider circuit generates the feedback voltage at a feedback node according to the regulated output voltage, and includes a string of resistors and a stabilization element. The string of resistors is coupled to the pass transistor and includes multiple resistors. The stabilization element is coupled to the resistors and receives the regulated output voltage.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: August 19, 2014
    Assignee: Mediatek Singapore Pte. Ltd.
    Inventors: Yingyi Liu, Kun Lan, Chih-Chien Huang, Yu-Kai Chou
  • Patent number: 8711025
    Abstract: A method for configuring a plurality of analog-to-digital converter (ADC) keys includes: utilizing a processor for determining a plurality of divided-voltages respectively corresponding to the Keys according to a plurality of voltage variation ranges respectively corresponding to the Keys; and calculating a plurality of resistive values of a voltage dividing model according to at least the divided-voltages, wherein the voltage dividing model has a plurality of voltage dividing configurations respectively corresponding to the keys.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: April 29, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Kun Lan, Yingyi Liu, Yu-Kai Chou
  • Publication number: 20130314262
    Abstract: A switch-driving circuit and a Digital-to-Analog Converter (DAC) using the switch-driving circuit are provided. The switch-driving circuit includes a main cell and a reference cell. The main cell includes a current source and a resistance-control component electronically connected to the current source. The reference cell is coupled to the current source and the resistance-control component, and includes a first loop, the first loop is configured to track a target reference voltage so as to provide at least one first control voltage to control a resistance change of the resistance-control component. The reference cell and the main cell are implemented by MOS transistors in place of capacitors which occupy an increased circuit area, rendering reduced circuit area for the switch-driving circuit, and decreasing manufacturing costs. Further, the switch-driving circuit outputs a voltage signal with reduced noise, increasing the performance of the Digital-to-Analog Converter.
    Type: Application
    Filed: March 15, 2013
    Publication date: November 28, 2013
    Applicant: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Cheng TAO, Yue FENG, Kun LAN, Yu-Kai CHOU
  • Publication number: 20130293403
    Abstract: An Analog to Digital Converter (ADC), an analog-to-digital conversion method, and an integrated circuit including the ADC. The ADC includes an input adjustment buffer stage, a sub-ADC, and a sample switch. The sample switch is coupled between the output node of the input adjustment buffer stage and the input node of the sub-ADC. When the sample switch is opened, the input adjustment buffer stage is configured to switch between a first work state and a second work state according to a predetermined rule, and to adjust an input voltage signal of the input adjustment buffer stage based on transitions between the first and second work states. When the sample switch is closed, the input adjustment buffer stage is configured to provide an adjusted voltage signal to the input node of the sub-ADC, and the sub-ADC is configured to perform an analog-to-digital conversion onto the adjusted voltage signal.
    Type: Application
    Filed: March 13, 2013
    Publication date: November 7, 2013
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Yingyi LIU, Yu-Kai CHOU, Kun LAN
  • Publication number: 20130201042
    Abstract: A method for configuring a plurality of analog-to-digital converter (ADC) keys includes: utilizing a processor for determining a plurality of divided-voltages respectively corresponding to the Keys according to a plurality of voltage variation ranges respectively corresponding to the Keys; and calculating a plurality of resistive values of a voltage dividing model according to at least the divided-voltages, wherein the voltage dividing model has a plurality of voltage dividing configurations respectively corresponding to the keys.
    Type: Application
    Filed: September 12, 2012
    Publication date: August 8, 2013
    Inventors: Kun Lan, Yingyi Liu, Yu-Kai Chou
  • Publication number: 20130076325
    Abstract: A voltage regulator includes a pass transistor, an operational amplifier and a voltage divider circuit. The pass transistor receives a supply voltage to generate a regulated output voltage according to a control signal. The operational amplifier generates the control signal according to a feedback voltage. The voltage divider circuit generates the feedback voltage at a feedback node according to the regulated output voltage, and includes a string of resistors and a stabilization element. The string of resistors is coupled to the pass transistor and includes multiple resistors. The stabilization element is coupled to the resistors and receives the regulated output voltage.
    Type: Application
    Filed: September 12, 2012
    Publication date: March 28, 2013
    Applicant: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Yingyi LIU, Kun LAN, Chih-Chien HUANG, Yu-Kai CHOU
  • Publication number: 20130027232
    Abstract: An analog-to-digital converter is provided and comprises a most significant bit (MSB) conversion module, a successive approximation register analog-to-digital converter (SAR ADC) module, and an operation module. The MSB conversion module receives an analog signal to be converted, and converts the analog signal to an MSB with M bits, and obtains a redundancy signal. The SAR ADC module is coupled to the MSB conversion module. The SAR ADC receives the redundancy signal and processes the redundancy signal to be a least significant bit (LSB) with N bits. The operation module is coupled to the MSB conversion module and the SAR ADC module. The operation module receives the MSB with the M bits and the LSB with the N bits and generates a first digital signal with (M+N) bits. Each of M and N is positive, and (M+N) is a positive integer.
    Type: Application
    Filed: July 27, 2012
    Publication date: January 31, 2013
    Applicant: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: Yingyi LIU, Yu-Kai CHOU, Kun LAN