Patents by Inventor William Walden

William Walden 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).

  • Publication number: 20220307708
    Abstract: An air purification device includes a housing configured to house a desiccant material filter and a fan coupled to the housing and configured to cause airflow to pass through the desiccant material filter. Moisture is to be collected from the airflow by the desiccant material filter. The moisture is to be removed from the desiccant material filter via one or more of heat or microwave energy.
    Type: Application
    Filed: March 14, 2022
    Publication date: September 29, 2022
    Inventors: Chang Yul Cha, Suk-Bae Cha, George Crandell, Craig Henricksen, William Walden
  • Publication number: 20220152264
    Abstract: A method includes identifying a schedule to operate a microwave enhanced air disinfection (MEAD) system and causing, based on the schedule, intermittent generation of microwave energy by a microwave generator of the MEAD system. A multi-component filter disposed in a housing of the MEAD system is configured to collect contaminants from airflow through the housing. At least a portion of the contaminants from the airflow is to be destroyed at least one of directly or indirectly via the microwave energy.
    Type: Application
    Filed: November 9, 2021
    Publication date: May 19, 2022
    Inventors: Chang Yul Cha, Suk-Bae Cha, George Crandell, Craig Henricksen, William Walden
  • Publication number: 20220152540
    Abstract: A microwave enhanced air disinfection (MEAD) device includes a housing and a microwave generator coupled to the housing. The microwave generator is configured to generate microwave energy. The MEAD device further includes a multi-component filter disposed in the housing. The multi-component filter is configured to collect contaminants from airflow. At least a portion of the contaminants from the airflow is to be destroyed at least one of directly or indirectly via the microwave energy.
    Type: Application
    Filed: November 9, 2021
    Publication date: May 19, 2022
    Inventors: Chang Yul Cha, Suk-Bae Cha, George Crandell, Craig Henricksen, William Walden
  • Publication number: 20060177392
    Abstract: An oil-based topical composition for use on the skin containing at least one compound from the class of retinoids, which are useful as medicinal agents, in an oleaginous solution composed substantially of non-ionic lipids, which are useful as vehicles for nonpolar compounds.
    Type: Application
    Filed: December 5, 2005
    Publication date: August 10, 2006
    Inventor: William Walden
  • Patent number: 6614294
    Abstract: A recurring noise filter for removing from a signal noise generated by parasitic coupling from a switching network. The filter contains an input filter, a sampling switch and an output filter. The input filter is a low pass filter which receives a signal containing noise generated by parasitic coupling from a switching network. The sampling switch is connected between the low pass filter and an output filter, with the sampling switch activating in response to the recurring switching of said switching network to sample the signal during the interval at which said noise does not occur within the signal. The output filter removes signals generated by the sampling switch from the sampled signal thereby generating a noise-filtered signal.
    Type: Grant
    Filed: May 28, 1999
    Date of Patent: September 2, 2003
    Assignee: Agere Systems Inc.
    Inventor: Robert William Walden
  • Patent number: 6539524
    Abstract: A method and apparatus are provided for matching the primary and parasitic capacitances of integrated circuit capacitors. The integrated circuit capacitors to be matched in accordance with the present invention can be of different sizes and connected in different circuit topologies. For example, the matching filter can have a differential filter capacitor structure and the reference circuit can have a single-ended filter configuration (or vice versa). The reference circuit to be matched is initially analyzed to identify the ratio of the primary capacitance, Cp, to the parasitic capacitance, Cg. Thereafter, a matching filter is selected with the desired topology and having the same ratio of the primary capacitance, Cp, to the parasitic capacitance, Cg, as the reference circuit (or a desired offset therefrom). A general technique is disclosed for analyzing capacitance circuits to identify the ratio of the primary capacitance, Cp, to the parasitic capacitance, Cg.
    Type: Grant
    Filed: May 10, 2000
    Date of Patent: March 25, 2003
    Assignee: Agere Systems Inc.
    Inventor: Robert William Walden
  • Patent number: 6271733
    Abstract: An integrated circuit includes an oscillator circuit for generating an output signal having a desired frequency. The oscillator circuit includes a capacitive device having a controllable capacitance value responsive to a control signal. A control circuit is connected to the oscillator circuit for controlling the capacitance value so that the oscillator circuit generates the output signal at the desired frequency. The control circuit includes a memory for storing a digital control word and a control signal generating circuit for converting the digital control word into the control signal for the capacitive device. Setting the desired frequency of the output signal is performed internal to the integrated circuit without requiring complex control circuitry for switching among various capacitors.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: August 7, 2001
    Assignee: Agere Systems Guardian Corp.
    Inventors: Ignacio Herrera Alzu, Rogelio Peon, Maarten Visee, Robert William Walden
  • Patent number: 6166592
    Abstract: An integrated transconductor circuit has an active load element and two parallel sets of transconductor stages. The active load element provides a high impedance without requiring a large area within the integrated transconductor circuit, and provides linear impedance when the active load devices are biased in the triode region of their respective characteristic curves. The multiple transconductor stages prevent saturation from reducing the dynamic range available at the output of the transconductor circuit. The parallel sets of transconductor stages are used to improve output linearity by reducing the differences between the threshold voltages of the serially-connected transconductor stages.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: December 26, 2000
    Assignee: Lucent Technologies Inc.
    Inventor: Robert William Walden
  • Patent number: 6049236
    Abstract: A method and system for a clock driver is described which can buffer an master clock directly, or generate a output clock signal having a balanced duty cycle which is the input clock frequency divided by a predetermined value. When a frequency control input, such as a rate signal, is switched, the clock output makes a glitchless transition from one frequency to the other. The clock driver includes a counter divider circuit with feedback to produce two signals related by a predetermined phase difference. The counter divider circuit employs predetermined logic delays by buffered gating controlled by the master clock, which produces two signals. These two signals act as "enable" control signals such that the timing of their rising and falling edges is arranged to never propagate through the clock divider circuit to become the edges of output clock. The master clock is gated with these two signals to provide two unbalanced signals which are synchronous to the input clock signal.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: April 11, 2000
    Assignee: Lucent Technologies Inc.
    Inventor: Robert William Walden
  • Patent number: 5896044
    Abstract: A level shifter circuit which is suitable for use in an integrated circuit converts an input logic signal having a first voltage potential to an output logic signal having a second voltage potential. For logic signals transmitted between sections of an integrated circuit operating with different supply voltages, the level shifter circuit allows reliable circuit operation between the sections when the voltage potential of the input logic signal is converted to the output logic signal having a higher voltage potential, the same voltage potential, or a lower voltage potential. The level shift circuit includes an inverter stage which drives a fully differential output stage, and the fully differential output stage includes two sections. Each section incorporates a fast switching pair of transistors connected in series across an output supply voltage and ground potential which act as an inverter and which provide an output node at the series connection.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: April 20, 1999
    Assignee: Lucent Technologies, Inc.
    Inventor: Robert William Walden