Patent ID: 6504927
Filing Date: 2003-01-07
Classification: H04M

Abstract:
A circuit for producing an output signal representative of a measured parameter of a telephone wireline comprising:tip and ring ports, adapted to be respectively coupled to said tip and ring leads of said telephone wireline; a tip-ring voltage measurement circuit coupled to said tip and ring ports, and being operative to produce an output voltage representative of a differential tip-ring voltage across said tip and ring ports; a modulator, coupled to said tip-ring voltage measurement circuit and being operative to modulate a periodic waveform in accordance with said output voltage produced by said tip-ring voltage measurement circuit; and an output circuit that is operative to couple said periodic waveform modulated by said modulator to a digital signal processing (DSP) circuit, and wherein said periodic waveform modulated by said modulator is not coupled to said tip and ring ports.