Patents by Inventor Jao-Chu Chao

Jao-Chu Chao 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).

  • Class-D amplifier with dual feedback loop
    Patent number: 7994853
    Abstract: A class-D amplifier with dual feedback loop scheme has a gain adjusting circuit, a second-order integrator, two comparators, a logic circuit and an output driver. Two differential output terminals of the class-D amplifier are connected to two differential amplifiers of the second-order integrator to construct a second-order feedback loop for offering second order noise shaping, eliminating non-linear components in the class-D amplifier, and also enhancing signal to noise and distortion ratio (SNDR). Further, distortion component existing in the differential signal output from the differential output terminals is amplified by the two differential amplifiers so as to improve the loop gain of the class-D amplifier. The differential signal processed by the two differential amplifiers also can be precisely adjusted.
    Type: Grant
    Filed: September 18, 2009
    Date of Patent: August 9, 2011
    Assignee: Eutech Microelectronics Inc.
    Inventor: Jao-Chu Chao
  • Single ended class-D amplifier with dual feedback loop scheme
    Patent number: 7982536
    Abstract: A single-ended class-D amplifier with dual feedback loop scheme has a gain adjusting circuit, a second-order integrator, two comparators, a logic circuit, an output driver and an inverter. The output driver cooperates with the inverter to produce a differential signal. The differential signal is input to the second-order integrator to construct a dual feedback differential loop to eliminate noise of output signals of the class-D amplifier, and offer enhanced signal to noise and distortion ratio (SNDR).
    Type: Grant
    Filed: September 18, 2009
    Date of Patent: July 19, 2011
    Assignee: Eutech Microelectronics Inc.
    Inventor: Jao-Chu Chao
  • SINGLE-ENDED CLASS-D AMPLIFIER WITH DUAL FEEDBACK LOOP SCHEME
    Publication number: 20110068869
    Abstract: A single-ended class-D amplifier with dual feedback loop scheme has a gain adjusting circuit, a second-order integrator, two comparators, a logic circuit, an output driver and an inverter. The output driver cooperates with the inverter to produce a differential signal. The differential signal is input to the second-order integrator to construct a dual feedback differential loop to eliminate noise of output signals of the class-D amplifier, and offer enhanced signal to noise and distortion ratio (SNDR).
    Type: Application
    Filed: September 18, 2009
    Publication date: March 24, 2011
    Applicant: EUTECH MICROELECTRONICS INC.
    Inventor: Jao-Chu CHAO
  • CLASS-D AMPLIFIER WITH DUAL FEEDBACK LOOP
    Publication number: 20110068870
    Abstract: A class-D amplifier with dual feedback loop scheme has a gain adjusting circuit, a second-order integrator, two comparators, a logic circuit and an output driver. Two differential output terminals of the class-D amplifier are connected to two differential amplifiers of the second-order integrator to construct a second-order feedback loop for offering second order noise shaping, eliminating non-linear components in the class-D amplifier, and also enhancing signal to noise and distortion ratio (SNDR). Further, distortion component existing in the differential signal output from the differential output terminals is amplified by the two differential amplifiers so as to improve the loop gain of the class-D amplifier. The differential signal processed by the two differential amplifiers also can be precisely adjusted.
    Type: Application
    Filed: September 18, 2009
    Publication date: March 24, 2011
    Applicant: EUTECH MICROELECTRONICS INC.
    Inventor: Jao-Chu CHAO