Communication system signaling circuit

摘要

A telephone switching system is disclosed which includes a digitally controllable multifunction signaling circuit responsive to commands from a central processor to generate or to receive subscriber line pulse signals of amplitude and duration specified by the processor commands. A bridge switch amplifier arrangement having an essentially constant voltage input signal and pulse width modulated control, is used to provide a substantially constant amplitude output signal. A two-stage access switch allows the signaling circuit to be time-shared among groups of subscriber lines.