Patents Represented by Attorney Christoffersen H.
  • Patent number: 4149124
    Abstract: A method and circuit for protecting the output stage of an amplifier from thermal overload. A normally-open, temperature sensitive switch is thermally coupled to the transistors in the output stage and electrically connected across a portion of the feedback resistance element of the amplifier, in one circuit embodiment. Whenever the temperature of the transistors reaches a predetermined threshold level, the switch closes and acts as a low resistance path across that portion of the feedback resistance element, thereby reducing the gain of the amplifier to a safe level which is zero in the preferred embodiment. Thereafter, when the temperature decreases below the predetermined threshold level, the switch automatically opens to restore normal operation of the amplifier.
    Type: Grant
    Filed: December 1, 1977
    Date of Patent: April 10, 1979
    Assignee: RCA Corporation
    Inventor: Miroslav Glogolja