| 摘要 |
<p>A circuit for detecting signals present on a bifilar voltage-supply and signal-transmission line, in which the signals are constituted by positive and negative variations of the supply potential of at least one of the wires of the line (2), comprises: a low-pass filter (20) connected to the two wires of the line in order to supply, at an output terminal of the filter, a constant reference potential (V+) substantially equal to the supply potential of a preselected one of the two wires, a first threshold comparator (21) having a reference input terminal (27) and a threshold input terminal (29) connected, respectively, to the output terminal (18) of the filter (20) and to the preselected wire of the two wires, and a second threshold comparator (22) having a reference input terminal (28) and a threshold input terminal (30) connected, respectively, to the preselected wire of the two wires and to the output terminal (18) of the filter (20). The circuit is relatively simple, does not require synchronization signals, and can be formed as an integrated circuit, taking up a limited area. <IMAGE></p> |
