IDT77222

The IDT77222 is a member of IDT's family of SAR products for Asynchronous Transfer Mode (ATM) networks. The IDT77222 performs both the ATM Adaptation Layer (AAL) Segmentation and Reassembly (SAR) function and the ATM layer protocol functions.

A Network Interface Card (NIC) or internetworking product based on the IDT77222 uses host memory, rather than local memory, to reassemble Convergence Sublayer Protocol Data Units (CS-PDUs) from ATM cell payloads received from the network. When transmitting, as CSPDUs become ready, they are queued in host memory and segmentedby the IDT77222 into ATM cell payloads. From this, the IDT77222 then creates complete 53-byte ATM cells which are sent through the network. The IDT77222's on-chip PCI bus master interface provides efficient, low latency DMA transfers with the host system, while its UTOPIA interface provides direct connection to PHY components used in 25.6 Mbps to 155 Mbps ATM networks.

The IDT77222 is fabricated using state-of-the-art CMOS technology, providing the highest levels of integration, performance and reliability, with the low-power consumption characteristics of CMOS.