Patents by Inventor Randy A. Chappel

Randy A. Chappel 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: 10812034
    Abstract: In an actuator driver array, each actuator driver includes a transition stage to initiate a state change of a driver output signal, a static stage to maintain the state change, and an isolation resistor to couple the driver output signal to an output node of the actuator driver during a static mode. In an array of pad capacitors, each pad capacitor has: a first terminal at a connector pad communicatively coupled to the output node; and a second terminal coupled to an RF ground rail. The isolation resistor and the pad capacitor form a low-pass filter to filter RF harmonics from a respective actuator driver to respective actuator circuitry, and to filter RF energy generated outside of the respective actuator driver to its output node. In an RF actuator array, a state of each element is controllable by a corresponding actuator driver in the actuator driver array.
    Type: Grant
    Filed: September 16, 2019
    Date of Patent: October 20, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel
  • Publication number: 20200014357
    Abstract: In an actuator driver array, each actuator driver includes a transition stage to initiate a state change of a driver output signal, a static stage to maintain the state change, and an isolation resistor to couple the driver output signal to an output node of the actuator driver during a static mode. In an array of pad capacitors, each pad capacitor has: a first terminal at a connector pad communicatively coupled to the output node; and a second terminal coupled to an RF ground rail. The isolation resistor and the pad capacitor form a low-pass filter to filter RF harmonics from a respective actuator driver to respective actuator circuitry, and to filter RF energy generated outside of the respective actuator driver to its output node. In an RF actuator array, a state of each element is controllable by a corresponding actuator driver in the actuator driver array.
    Type: Application
    Filed: September 16, 2019
    Publication date: January 9, 2020
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel
  • Patent number: 10418961
    Abstract: In an actuator driver array, each actuator driver includes a transition stage to initiate a state change of a driver output signal, a static stage to maintain the state change, and an isolation resistor to couple the driver output signal to an output node of the actuator driver during a static mode. In an array of pad capacitors, each pad capacitor has: a first terminal at a connector pad communicatively coupled to the output node; and a second terminal coupled to an RF ground rail. The isolation resistor and the pad capacitor form a low-pass filter to filter RF harmonics from a respective actuator driver to respective actuator circuitry, and to filter RF energy generated outside of the respective actuator driver to its output node. In an RF actuator array, a state of each element is controllable by a corresponding actuator driver in the actuator driver array.
    Type: Grant
    Filed: November 10, 2017
    Date of Patent: September 17, 2019
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel
  • Publication number: 20180091110
    Abstract: In an actuator driver array, each actuator driver includes a transition stage to initiate a state change of a driver output signal, a static stage to maintain the state change, and an isolation resistor to couple the driver output signal to an output node of the actuator driver during a static mode. In an array of pad capacitors, each pad capacitor has: a first terminal at a connector pad communicatively coupled to the output node; and a second terminal coupled to an RF ground rail. The isolation resistor and the pad capacitor form a low-pass filter to filter RF harmonics from a respective actuator driver to respective actuator circuitry, and to filter RF energy generated outside of the respective actuator driver to its output node. In an RF actuator array, a state of each element is controllable by a corresponding actuator driver in the actuator driver array.
    Type: Application
    Filed: November 10, 2017
    Publication date: March 29, 2018
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel
  • Patent number: 9887680
    Abstract: A dual-mode driver includes a transition stage and a static stage. The transition stage switches a bias voltage or an RF ground potential to an output pad to change the state of an RF actuator device connected at the output pad. After waiting a predetermined period of time for the RF actuator device to change state, the transition stage of the driver is disabled. A high-side or low-side static stage transistor maintains the driver output state through an isolation resistor. The isolation resistor and a capacitor formed at the driver output pad form an RC low-pass filter to block spurious noise generated at the driver. The RC filter also blocks RF energy that might otherwise enter the actuator driver from the actuator. Some embodiments also include a second RC filter located proximate to the output pad to prevent RF energy generated in the RF actuator from entering the driver.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: February 6, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel
  • Publication number: 20160156337
    Abstract: A dual-mode driver includes a transition stage and a static stage. The transition stage switches a bias voltage or an RF ground potential to an output pad to change the state of an RF actuator device connected at the output pad. After waiting a predetermined period of time for the RF actuator device to change state, the transition stage of the driver is disabled. A high-side or low-side static stage transistor maintains the driver output state through an isolation resistor. The isolation resistor and a capacitor formed at the driver output pad form an RC low-pass filter to block spurious noise generated at the driver. The RC filter also blocks RF energy that might otherwise enter the actuator driver from the actuator. Some embodiments also include a second RC filter located proximate to the output pad to prevent RF energy generated in the RF actuator from entering the driver.
    Type: Application
    Filed: December 2, 2014
    Publication date: June 2, 2016
    Inventors: Michael John Shay, Jialei Xu, Randy A. Chappel