LOW-PASS FILTER WHICH IS INTENDED FOR TELEPHONE LINES THAT ARE ADAPTED FOR ADSL TRANSMISSION

摘要

The invention relates to a low-pass filter (500) which is made in part in the form of an ASIC-type integrated circuit (503) which is disposed in parallel between two transmission lines (501; 502) forming the telephone line (L). A decoupling capacitance (504) can be disposed in series with the ASIC (503), thereby preventing direct current from passing through the ASIC (503) and preventing said ASIC from being subjected to an excessive voltage. According to the invention, an inductance (L1; L2) is disposed on each transmission line (501; 502) in order to provide the low-pass filter (500) with a sufficient input impedance when signals in the ADSL frequency band are circulating.