XTA-0808 is a high-speed, low latency ASIC solution for connecting Ethernet LAN to the WAN via ATM technologyby converting Ethernet frames from/to ATM cells.

XTA-0808 provides transparent, full duplex operation of ATM cell to Ethernet frame conversion at data rate upto 40Mbps per port. The conversion rate can reach 97Mbps for downstream and 85Mbps for upstream when only one port of the XTA-0808 is used.

Three XTA-0808 and one 24-port switch controller can be integrated to form a 24-channel EoDSL CO device. Individual VC with embedded table of VCI/VPI for path identification is supported for each channel. The Utopia interface of XTA-0808 is implemented on a port-to-port basis, making it more cost effective and flexible.

XTA-0808 is manufactured by TSMC using 0.35-micro process and operated on a single 3.3V power. It is available in a compact and low profile 128-pin TQFP package.

XTA-0808 is fully compliant with RFC 2684 bridge mode for LLC Encapsulation (multiplexing of multiple protocols over a single ATM VC) and VC Multiplexing (each ATM VC carries PDUs of exactlyone protocol type). AAL5 is also supported for PDU SAR (Segmentation AndRe-assembly).

XTA-0808 supports up to eight channels of simultaneous conversion of ATM cell to Ethernet frame. It supports Reversed SSSMII interface for Ethernet connectivity and Utopia master interface for ATM circuits.

When OAM function is needed, one optional external 8051 uP can support the function for up to three XTA-0808.

·  Very Low Latency: min 6/6 us (DS/US)

    ■ Ideal for VoIP and Video On Demand

·  High Throughput:

    ■ Minimum: per port 40Mbps throughput for the downstream and the upstream paths

    ■ Maximum: 97Mbps (downstream) / 85Mbps (upstream) when only using a single port

·  Cost Effective: Can be integrated with XTE-2402G to form a highly cost effective IPDSLAM line card solution

·  Optional external μP (8051) for OAM function

·  No software effort required for SAR

·  14mm x 14mm compact package

·  Single chip 8-port ATM Cell from/to Ethernet Frame converter

·  RFC 2684 bridge mode (LLC / VC-MUX encapsulation)

·  AAL5 SAR (Segmentation and Re-Assembly)

·  MDC / MDIO for mode setting

·  Embedded table supports configurable VCI / VPI per DSL port

·  Reversed SSSMII interface and 1 Utopia interface on eight 100Mbps full duplex Ethernet ports

·  IEEE 802.3x flow control compliant

·  Downstream memory buffer size up to 16 packets and 8 packets for upstream

·  Memory segmentation by page, 256 bytes per page

·  Embedded 48.6KB memory for packet / cell buffer

·  62.5MHz system frequency

·  Utopia Interface

    ■ One Utopia Level 2 interface supports up to 8 xDSL channels

    ■ 8-bits Utopia Level 2 data bus with clock speed up to 40MHz

·  0.35um, single 3.3V

·  128 pins TQFP