A programmable SLIC consisting of both SCF and DSP technologies with 30dB return loss characteristics

A subscriber line interface circuit(SL1C) LSI with on-chip programmable line termination and hybrid balance impedances is presented. Both switched capacitor filtering(SCF) and digital signal processing(DSP) technologies are applied to improve transmission characteristics. Our simulation results confirm more than 30dB of 2- wire and 4-wire return losses for most of worldwide subscriber lines without any external precision elements.