Video image clarity enhancement signal production device for video pre-amplification circuit, has differential transconductance stage having bias current directly proportional to active component of video signal

摘要

The device has a differential transconductance stage for processing a video signal. A bias current of the differential bias current stage is directly proportional to an active component of the video signal for producing a clipping signal for the enhancement of clarity of the video signal at the level of black. Two controlled current sources are coupled to respective transistors of the transconductance stage. An independent claim is also included for a video pre-amplification circuit using the enhancement device of the invention.