Verfahren und Schaltung zur Reduktion von Verlustleistung in der DC-Abschlusseinheit

摘要

A DC termination device, particularly adapted for use in a device coupled to a two wire telecommunications system, controls the tip-to-ring current through the telecommunications device by means of a voltage controlled current source (12). The control voltage for the voltage controlled current source is provided by digital signal processing (14) of the tip-to-ring voltage such that the tip-to-ring current is linearly proportional to the tip-to-ring voltage when the voltage is below a specified threshold level, but is maintained constant when the tip-to-ring voltage is over the threshold voltage. Preferably, the constant current is the minimum adequate current needed for operation.