Patents by Inventor Thayamkulangara R. Viswanathan

Thayamkulangara R. Viswanathan 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: 4484089
    Abstract: Many signal processing applications of practical importance (for example, continuous-signal filtering) require high-precision temperature-insensitive transconductance elements. In accordance with one feature of this invention, a reference transconductance element is included in a control loop. The element consists of a MOSFET device or a MOSFET circuit in the loop. In the loop, the transconductance of the reference element is determined solely by the value and switching period of a switched-capacitor. The transconductance of the element is in effect thereby precisely matched against the conductance of the switched-capacitor.As the temperature of the chip varies, a control voltage is generated in the loop to maintain the transconductance of the reference element constant. This same control voltage is applied to other similar elements included in circuits (for example, filters) on the chip. In that way, the transconductances of these other elements are also matched to that of the switched-capacitor.
    Type: Grant
    Filed: August 19, 1982
    Date of Patent: November 20, 1984
    Assignee: AT&T Bell Laboratories
    Inventor: Thayamkulangara R. Viswanathan