The IDT77V1253 is a member of IDT's family of products supporting Asynchronous Transfer Mode (ATM) data communications and networking. The IDT77V1253 implements the physical layer for 25.6 Mbps ATM, connecting three serial copper links (UTP Category 3) to one ATM layer device such as a SAR or a switch ASIC. The IDT77V1253 also operates at 51.2 Mbps, and is well suited to backplane driving applications. The 77V1253-to-ATM layer interface is selectable as one of three options: 16-bit UTOPIA Level 2, 8-bit UTOPIA Level 1 Multi-PHY, or triple 4-bit DPI (Data Path Interface).