MVTX2604
Data Sheet
Description
The MVTX2604 is a high density, low cost, high performance, non-blocking Ethernet switch chip. A single chip
provides 24 ports at 10/100 Mbps, 2 ports at 1000 Mbps and a CPU interface for managed and unmanaged switch
applications. The Gigabit ports can also support 10/100 M and 2 G stacking modes.
The chip supports up to 64 K MAC addresses and up to 255 port-based Virtual LANs (VLANs). The centralized
shared memory architecture permits a very high performance packet forwarding rate at up to 9.524 M packets per
second at full wire speed. The chip is optimized to provide low-cost, high-performance workgroup switching.
Two Frame Buffer Memory domains utilize cost-effective, high-performance synchronous SRAM with aggregate
bandwidth of 12.8 Gbps to support full wire speed on all ports simultaneously. In the 24+2 stacking (2 G per
stacking port) configuration, 2 ZBT domains are needed.
With delay bounded, strict priority, and/or WFQ transmission scheduling, and WRED dropping schemes, the
MVTX2604 provides powerful QoS functions for various multimedia and mission-critical applications. The chip
provides 4 transmission priorities (8 priorities per Gigabit port) and 2 levels of dropping precedence. Each packet is
assigned a transmission priority and dropping precedence based on the VLAN priority field in a VLAN tagged
frame, or the DS/TOS field, or the UDP/TCP logical port fields in IP packets. The MVTX2604 recognizes a total of
16 UDP/TCP logical ports, 8 hard-wired and 8 programmable (including one programmable range).
The MVTX2604 supports 3 groups of port trunking/load sharing. One group is dedicated to the two Gigabit ports,
and the other two groups to 10/100 ports, where each 10/100 group can contain up to 4 ports. Port trunking/load
sharing can be used to group ports between interlinked switches to increase the effective network bandwidth.
In half-duplex mode all ports support backpressure flow control to minimize the risk of losing data during long
activity bursts. In full-duplex mode, IEEE 802.3x flow control is provided. The MVTX2604 also supports a per-
system option to enable flow control for best effort frames, even on QoS-enabled ports.
The Physical Coding Sublayer (PCS) is integrated on-chip to provide a direct 10-bit interface for connection to
SERDES chips. The PCS can be bypassed to provide a GMII interface.
Statistical information for SNMP and the Remote Monitoring Management Information Base (RMON MIB) are
collected independently for all ports. Access to these statistical counters/registers is provided via the CPU interface.
SNMP Management frames can be received and transmitted via the CPU interface creating a complete network
management solution.
The MVTX2604 is fabricated using 0.25 micron technology. Inputs, however, are 3.3 V tolerant, and the outputs are
capable of directly interfacing to LVTTL levels. The MVTX2604 is packaged in a 553-pin Ball Grid Array package.
3
Zarlink Semiconductor Inc.