The Dual ProSLIC is a series of low-voltage CMOS devices that integrate both SLIC and codec functionality into a single IC to provide a complete dual-channel analog telephone interface in accordance with all relevant LSSGR, ITU, and ETSI specifications. The Si3220 includes internal ringing generation to eliminate centralized ringers and ringing relays, and the Si3225 supports centralized ringing for long loop and legacy applications. On-chip subscriber loop and audio testing allows remote diagnostics and fault detection with no external test equipment or relays. The Si3220 and Si3225 operate from a single 3.3 or 5 V supply and interface to standard PCM/SPI or GCI bus digital interfaces. The Si3200 linefeed interface IC performs all high-voltage functions and operates from a 3.3 V or 5 V supply as well as single or dual battery supplies up to 100 V. The Si3220 and Si3225 are available in a 64-pin thin quad flat package (TQFP), and the Si3200 is available in a thermally-enhanced 16-pin small outline (SOIC) package.