Patents by Inventor Denny E. Henson

Denny E. Henson 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).

  • PWM DAC with improved linearity and insensitivity to switch resistance
    Patent number: 11316528
    Abstract: A pulse width modulation (PWM) digital-to-analog conversion circuit includes switches 102, 104, 114, 116 controlled by a first PWM signal, and switches 106, 108, 110, 112 controlled by a second PWM signal. A first operational amplifier (op-amp) includes a first input coupled to an output of a filter, and a second input coupled to an output of the first op-amp. During a first time period, an output of a second op-amp is coupled to an input of the filter via switches 102 and 104, and an output of a third op-amp is coupled to the output of the first op-amp via switches 114 and 116. During a second time period, the output of the second op-amp is coupled to the output of the first op-amp via switches 106 and 108, and an output of the third op-amp is coupled to the input of the filter via switches 110 and 112.
    Type: Grant
    Filed: January 21, 2021
    Date of Patent: April 26, 2022
    Assignee: Fluke Corporation
    Inventor: Denny E. Henson
  • PWM DAC WITH IMPROVED LINEARITY AND INSENSITIVITY TO SWITCH RESISTANCE
    Publication number: 20210234552
    Abstract: A pulse width modulation (PWM) digital-to-analog conversion circuit includes switches 102, 104, 114, 116 controlled by a first PWM signal, and switches 106, 108, 110, 112 controlled by a second PWM signal. A first operational amplifier (op-amp) includes a first input coupled to an output of a filter, and a second input coupled to an output of the first op-amp. During a first time period, an output of a second op-amp is coupled to an input of the filter via switches 102 and 104, and an output of a third op-amp is coupled to the output of the first op-amp via switches 114 and 116. During a second time period, the output of the second op-amp is coupled to the output of the first op-amp via switches 106 and 108, and an output of the third op-amp is coupled to the input of the filter via switches 110 and 112.
    Type: Application
    Filed: January 21, 2021
    Publication date: July 29, 2021
    Inventor: Denny E. Henson