Method and apparatus providing high speed video signal limiting

摘要

An input signal (IN) and a threshold signal (Vt) are coupled to an output terminal (2) via the base-emitter paths of first (Q1) and second (Q2) transistors having respective collector electrodes connected to a supply voltage source (3). The output terminal (2) is coupled to a source of reference potential (4) via a first resistor (Re) and is coupled via a second resistor (Rd) to a selected plate of a capacitor (C1) that is connected between the collector and base electrodes of the second transistor (Q2). Circuit impedances are scaled such that Re>Rd>R1 wherein Re and Rd are the values of the first and second resistors, respectively, and R1 is a component of the output impedance of the threshold signal source (5). <IMAGE>