Circuit for generating a pulse-shaped signal for a communication line

摘要

The transmitter (4) has a feedback current generator (24) and a charging current generator (25) comprising of a feedback loop responsive to a capacitor voltage (VO) for generating a feedback current (IE) having a continuous magnitude that is a progressive function of the capacitor voltage. The charging current supplied to a capacitor (19) is a function of the feedback current. The capacitor is included in a signal generator which also includes a signal producing unit (9) responsive to the capacitor voltage across the capacitor for applying a switched signal on a communication line. The feedback current generator and charging current generator respond to the input signal (TX) for supplying charging current to the capacitor so as to define the edge of the switched signal.