Patents by Inventor Jen-Che Tsai

Jen-Che Tsai 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: 9876517
    Abstract: A radio frequency (RF) receiver includes a digital tuning engine; and I-path and Q-path analog filters, tuned by the digital tuning engine. The digital tuning engine gets an I/Q imbalance difference, and the digital tuning engines tunes the I-path analog filter and/or the Q-path analog filter based on the I/O imbalance difference.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: January 23, 2018
    Assignee: MEDIATEK INC.
    Inventors: Sheng-Hong Yan, Sheng-Hao Chen, Paul Cheng Po Liang, Jen-Che Tsai
  • Patent number: 9385740
    Abstract: A SAR ADC including a comparator, an input switch unit, a positive conversion capacitor array, a negative conversion capacitor array, and a SAR controller is provided. The input switch unit alternately couples and decouples a differential analog input signal to the comparator. The positive and negative conversion capacitor arrays sample the differential analog input signal during the sampling phase. The SAR controller resets the switches in the capacitor arrays at the end of the sampling phase to change the sampled voltage into a residual signal, generates an intermediate digital code to control the switches during the conversion phase according to an output of the comparator to convert the residual signal to the intermediate digital code, generates the digital code according to the intermediate digital code, and uses an inverted intermediate digital code to control the switches at the end of the conversion phase.
    Type: Grant
    Filed: October 22, 2015
    Date of Patent: July 5, 2016
    Assignee: MEDIATEK INC.
    Inventors: Chi Yun Wang, Jen-Che Tsai, Shu-Wei Chu
  • Publication number: 20160134300
    Abstract: A SAR ADC including a comparator, an input switch unit, a positive conversion capacitor array, a negative conversion capacitor array, and a SAR controller is provided. The input switch unit alternately couples and decouples a differential analog input signal to the comparator. The positive and negative conversion capacitor arrays sample the differential analog input signal during the sampling phase. The SAR controller resets the switches in the capacitor arrays at the end of the sampling phase to change the sampled voltage into a residual signal, generates an intermediate digital code to control the switches during the conversion phase according to an output of the comparator to convert the residual signal to the intermediate digital code, generates the digital code according to the intermediate digital code, and uses an inverted intermediate digital code to control the switches at the end of the conversion phase.
    Type: Application
    Filed: October 22, 2015
    Publication date: May 12, 2016
    Inventors: Chi Yun Wang, Jen-Che Tsai, SHU-WEI CHU
  • Publication number: 20150303957
    Abstract: A radio frequency (RF) receiver includes a digital tuning engine; and I-path and Q-path analog filters, tuned by the digital tuning engine. The digital tuning engine gets an I/Q imbalance difference, and the digital tuning engines tunes the I-path analog filter and/or the Q-path analog filter based on the I/Q imbalance difference.
    Type: Application
    Filed: June 30, 2015
    Publication date: October 22, 2015
    Inventors: Sheng-Hong Yan, Sheng-Hao Chen, Paul Cheng Po Liang, Jen-Che Tsai
  • Patent number: 9100078
    Abstract: A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: August 4, 2015
    Assignee: MEDIATEK INC.
    Inventors: Sheng-Hong Yan, Sheng-Hao Chen, Paul Cheng Po Liang, Jen-Che Tsai
  • Patent number: 9094034
    Abstract: A digital to analog converting system, which comprises: a first data converting circuit, for receiving a first digital data stream transmitted at a first clock frequency, for converting the first digital data stream to a plurality of second digital data streams transmitted at a second clock frequency, and for outputting the second digital data streams in parallel; a second data converting circuit, for receiving the second digital data streams from the first data converting circuit, and for converting the second digital data streams to a third digital data stream transmitted at a third clock frequency; and a first digital to analog converter, for converting the third digital data stream to a first output analog data stream. The second clock frequency is lower than the first clock frequency and the third clock frequency.
    Type: Grant
    Filed: September 10, 2014
    Date of Patent: July 28, 2015
    Assignee: MEDIATEK INC.
    Inventors: Sheng-Hao Chen, Yen-Chuan Huang, Min-Hua Wu, Chun-Hao Liao, Hung-Pin Ma, Tzu-Hao Yu, Jen-Che Tsai
  • Publication number: 20150123830
    Abstract: A digital to analog converting system, which comprises: a first data converting circuit, for receiving a first digital data stream transmitted at a first clock frequency, for converting the first digital data stream to a plurality of second digital data streams transmitted at a second clock frequency, and for outputting the second digital data streams in parallel; a second data converting circuit, for receiving the second digital data streams from the first data converting circuit, and for converting the second digital data streams to a third digital data stream transmitted at a third clock frequency; and a first digital to analog converter, for converting the third digital data stream to a first output analog data stream. The second clock frequency is lower than the first clock frequency and the third clock frequency.
    Type: Application
    Filed: September 10, 2014
    Publication date: May 7, 2015
    Inventors: Sheng-Hao Chen, Yen-Chuan Huang, Min-Hua Wu, Chun-Hao Liao, Hung-Pin Ma, Tzu-Hao Yu, Jen-Che Tsai
  • Patent number: 8669896
    Abstract: A method of controlling a successive-comparing-register analog-to-digital convertor (SAR ADC) is provided. Based upon the method, the SAR ADC receives a conversion clock that controls a conversion rate of the SAR ADC.
    Type: Grant
    Filed: June 11, 2012
    Date of Patent: March 11, 2014
    Assignee: Mediatek Inc.
    Inventors: Jen-Che Tsai, Chao-Hsin Lu
  • Patent number: 8629793
    Abstract: A continuous-time delta-sigma Analog to Digital Converter (ADC) includes: a loop filter, for receiving and noise-shaping an analog input signal, and outputting a first loop voltage; a first summing resistor, for transforming a first feedback current to be a first feedback voltage, and summing the first loop voltage and the first feedback voltage so as to generate a first summing voltage, wherein the first summing voltage is equal to a sum of the first loop voltage and the first feedback voltage; a quantizer, for outputting a digital output signal according to the first summing voltage; and a current Digital to Analog Converter (DAC), for generating the first feedback current according to the digital output signal.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: January 14, 2014
    Assignee: Mediatek Inc.
    Inventor: Jen-Che Tsai
  • Publication number: 20130266102
    Abstract: A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit.
    Type: Application
    Filed: March 13, 2013
    Publication date: October 10, 2013
    Applicant: MEDIATEK Inc.
    Inventors: Sheng-Hong Yan, Sheng-Hao Chen, Cheng-Po Liang, Jen-Che Tsai
  • Patent number: 8462960
    Abstract: A signal processing system and related method are disclosed. The signal processing system includes a signal processing module, powered by a low supply voltage, for processing signals; and an interface module, coupled to the signal processing module, powered by a high supply voltage, for outputting signals generated from the signal processing module; wherein the interface module comprises a plurality of high-voltage functional blocks integrated therein, and each of the functional blocks is configured to perform a predetermined interface functionality. In this way, the bill-of-material (BOM) cost can be reduced.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: June 11, 2013
    Assignee: Mediatek Inc.
    Inventors: Sheng-Jui Huang, Yung-Yu Lin, Jen-Che Tsai, Tzueng-Yau Lin, Yau-Wai Wong, Chih-Horng Weng, Chi-Hui Wang
  • Publication number: 20130099953
    Abstract: A method of controlling a successive-comparing-register analog-to-digital convertor (SAR ADC) is provided. Based upon the method, the SAR ADC receives a conversion clock that controls a conversion rate of the SAR ADC.
    Type: Application
    Filed: June 11, 2012
    Publication date: April 25, 2013
    Inventors: Jen-Che Tsai, Chao-Hsin Lu
  • Patent number: 8218793
    Abstract: An apparatus and a muting circuit. The apparatus comprises an amplifier, a mute circuit, a pull-down circuit, and a power detection circuit. The amplifier receives a power supply voltage and a common mode voltage, and amplifies an audio input signal to generate an audio output signal. The mute circuit, coupled to the amplifier, conducts the audio output signal to about ground level upon receiving a mute signal. The pull-down circuit, coupled to the amplifier, pulls the common mode voltage to about ground level upon receiving a pull-down signal. The power detection circuit, coupled to the mute circuit and the pull-down circuit, detects power-up or power-down of the power supply voltage, and generates the mute signal and a pull-down signal according to the power-up or power-down operation.
    Type: Grant
    Filed: December 4, 2007
    Date of Patent: July 10, 2012
    Assignee: Mediatek Inc.
    Inventors: Jen-Che Tsai, Yau-Wai Wong
  • Patent number: 8171335
    Abstract: A clock timing calibration circuit includes a clock timing adjusting unit and a calibration control unit. The clock timing adjusting unit is for receiving an incoming reference clock signal and selectively adjusting the received reference clock signal to generate a first clock signal according to a calibration control signal. The incoming reference clock has a predetermined phase and a predetermined frequency, The calibration control unit is for checking if the phase difference between the first clock signal and a second clock signal satisfies a predetermined criterion, and for adjusting the calibration control signal when the phase difference between the first clock signal and the second clock signal does not satisfy the predetermined criterion. The predetermined criterion is to check if the phase difference falls within a specific range associated with a clock period of one of the first clock signal and the second clock signal.
    Type: Grant
    Filed: June 8, 2009
    Date of Patent: May 1, 2012
    Assignee: Mediatek Inc.
    Inventor: Jen-Che Tsai
  • Publication number: 20110285562
    Abstract: A continuous-time delta-sigma Analog to Digital Converter (ADC) includes: a loop filter, for receiving and noise-shaping an analog input signal, and outputting a first loop voltage; a first summing resistor, for transforming a first feedback current to be a first feedback voltage, and summing the first loop voltage and the first feedback voltage so as to generate a first summing voltage, wherein the first summing voltage is equal to a sum of the first loop voltage and the first feedback voltage; a quantizer, for outputting a digital output signal according to the first summing voltage; and a current Digital to Analog Converter (DAC), for generating the first feedback current according to the digital output signal.
    Type: Application
    Filed: August 3, 2011
    Publication date: November 24, 2011
    Inventor: Jen-Che Tsai
  • Publication number: 20110221618
    Abstract: A continuous-time delta-sigma Analog to Digital Converter (ADC) with a compact structure comprises a loop filter, a summing circuit, a quantizer, and a current Digital to Analog Converter (DAC). The loop filter is utilized for receiving and noise-shaping an analog input signal, and accordingly outputting a positive and a negative loop voltages. The summing circuit comprises a positive and a negative summing resistors. The summing resistors are utilized for transforming a positive and negative feedback currents to be a positive and a negative feedback voltages, and summing the loop voltages and the feedback voltages so as to generate a positive and a negative summing voltages, respectively. The quantizer is utilized for outputting a digital output signal according to a difference between the positive and the negative summing voltages. The current DAC is utilized for generating the positive and the negative feedback currents according to the digital output signal.
    Type: Application
    Filed: March 14, 2010
    Publication date: September 15, 2011
    Inventor: Jen-Che Tsai
  • Patent number: 8018365
    Abstract: A continuous-time delta-sigma Analog to Digital Converter (ADC) with a compact structure comprises a loop filter, a summing circuit, a quantizer, and a current Digital to Analog Converter (DAC). The loop filter is utilized for receiving and noise-shaping an analog input signal, and accordingly outputting a positive and a negative loop voltages. The summing circuit comprises a positive and a negative summing resistors. The summing resistors are utilized for transforming a positive and negative feedback currents to be a positive and a negative feedback voltages, and summing the loop voltages and the feedback voltages so as to generate a positive and a negative summing voltages, respectively. The quantizer is utilized for outputting a digital output signal according to a difference between the positive and the negative summing voltages. The current DAC is utilized for generating the positive and the negative feedback currents according to the digital output signal.
    Type: Grant
    Filed: March 14, 2010
    Date of Patent: September 13, 2011
    Assignee: Mediatek Inc.
    Inventor: Jen-Che Tsai
  • Publication number: 20100066422
    Abstract: A clock timing calibration circuit includes a clock timing adjusting unit and a calibration control unit. The clock timing adjusting unit is for receiving an incoming reference clock signal and selectively adjusting the received reference clock signal to generate a first clock signal according to a calibration control signal. The incoming reference clock has a predetermined phase and a predetermined frequency, The calibration control unit is for checking if the phase difference between the first clock signal and a second clock signal satisfies a predetermined criterion, and for adjusting the calibration control signal when the phase difference between the first clock signal and the second clock signal does not satisfy the predetermined criterion. The predetermined criterion is to check if the phase difference falls within a specific range associated with a clock period of one of the first clock signal and the second clock signal.
    Type: Application
    Filed: June 8, 2009
    Publication date: March 18, 2010
    Inventor: Jen-Che Tsai
  • Patent number: 7663525
    Abstract: A digital to analog converter including a first capacitor, a second capacitor, an operational amplifier, and a switch is disclosed. During a first period, the first capacitor stores a first voltage and the second capacitor stores a second voltage. The operational amplifier comprises an input and an output. The switch parallels the first and the second capacitors with the operational amplifier at the input and output according to a digital signal during a second period.
    Type: Grant
    Filed: July 30, 2007
    Date of Patent: February 16, 2010
    Assignee: Mediatek Inc.
    Inventor: Jen-Che Tsai
  • Publication number: 20090296950
    Abstract: A signal processing system and related method are disclosed. The signal processing system includes a signal processing module, powered by a low supply voltage, for processing signals; and an interface module, coupled to the signal processing module, powered by a high supply voltage, for outputting signals generated from the signal processing module; wherein the interface module comprises a plurality of high-voltage functional blocks integrated therein, and each of the functional blocks is configured to perform a predetermined interface functionality. In this way, the bill-of-material (BOM) cost can be reduced.
    Type: Application
    Filed: May 28, 2008
    Publication date: December 3, 2009
    Inventors: Sheng-Jui Huang, Yung-Yu Lin, Jen-Che Tsai, Tzueng-Yau Lin, Yau-Wai Wong, Chih-Horng Weng, Chi-Hui Wang