A subscriber line interface circuit apparatus includes a linefeed circuit and a subscriber line control circuit (SLCC). In an embodiment, the linefeed circuit includes a signal conversion circuit which provides a differential mode signal and a common mode signal in response to at least a tip signal and a ring signal from the subscriber loop. The linefeed circuit includes a tip control circuit and a ring control circuit. In an embodiment, the SLCC is provided in a single integrated circuit chip and is coupled to the linefeed circuit which isolates the SLCC from the tip or ring signals. The SLCC includes a first and a second differential mode inputs for receiving the differential mode signal, and a common-mode input for receiving the common-mode signal. In an embodiment, the SLCC also provides various tip control signals and ring control signals to the tip control circuit and the ring control circuit, respectively.