The MAX4670 is an integrated T1/E1/J1 analog protection switch for 1+1 and N+1 line-card redundancy applications. It protects two T1/E1/J1 ports by combining eight SPDT switches in a single package. The switch is optimized for high-return loss and pulse-template performance in T1/E1/J1 long-haul and short-haul applications. The part offers built-in chip-side surge protection capability for short-haul intrabuilding applications. The MAX4670 replaces two diode arrays or two transient voltage suppressors (TVSs) and four dual-SPDT relays, significantly reducing board space and simplifying PC board routing. The MAX4670 pinout is targeted for T1/E1/J1 applications, resulting in a simplified layout when interfacing with standard line transformers and line interface units (LIUs).