Patent ID: 6122367
Filing Date: 2000-09-19
Classification: H04M

Abstract:
A subscriber line interface circuit, comprisingmeans adapted to apply to a line, associated with the line interface circuit, a substantially constant line current of a first predetermined value for line voltages up to a first voltage having an absolute value which, by a predetermined amount, is lower than a supply voltage of the line interface circuit,means adapted to apply to the line, a line current which is inversely proportional to the line voltage and of a value between said first predetermined value and a second predetermined, lower value for line voltages between the first voltage and a second voltage having an absolute value which, by a predetermined amount, is higher than the first voltage,means adapted to apply to the line, a substantially constant line current of the second predetermined value for line voltages between the second voltage and a third voltage having an absolute value which, by a predetermined amount, is higher than the second voltage, andmeans adapted to maintain the line voltage substantially constant at the third voltage for line currents of lower value than said second predetermined value.