DESCRIPTION

The PM3351 is a low-cost, highly integrated stand-alone single-chip switching device for 10/100 Mbit/s Ethernet (IEEE 802.3u, IEEE 802.12) switching and bridging applications. The device supports all processing required for switching Ethernet packets between the on-chip Medium Independent Interface (MII) port and the built-in 1 Gbit/s expansion port, to which other PM3351 (ELAN 1x100) or PM3350 (ELAN 8x10) devices may be attached.

FEATURES

• Single-chip, 1-port, full duplex or half duplex, 10/100BaseT switching device for

low-cost unmanaged and managed networks.

• On-chip 50 MHz RISC CPU processor core, multi-channel DMA controller,

MAC-layer interface logic, FIFOs, PCI-based expansion port and a flexible

memory controller.

• CPU supports background applications running on local OS (e.g., SNMP or

RMON), and real-time data oriented applications (e.g., frame forwarding and

filtering decisions).

• Performs frame switching at a rate of 200 Mbit/s (full duplex), 100 Mbit/s (half

duplex).

• Fully compatible with the PM3350, 8-port 10 Mbit/s switch device; may be used

to create a compact and inexpensive mixed 10/100 Mbit/s switching hub.

• Store-and-forward operation with full error checking and filtering.

• Filtering and switching at wire rates (up to 148,800 packets per second),

supporting a mix of Ethernet and IEEE 802.3 protocols.

• Expansion port supports a peak system bandwidth of 1 Gbit/s, and is compatible

with industry-standard PCI bus (version 2.1).

• Performs all address learning, address table management and aging functions

for up to 32,768 MAC addresses (limited by external memory). Address

learning rate of up to 100,000 addresses per second.

• Maximum broadcast/multicast at wire rates with configurable broadcast storm

rate limiting.

• Low-latency operation in both unicast and broadcast modes.

• Implements the Link Partition function to isolate malfunctioning segments or

hosts.

• IEEE 802.1d compliant spanning-tree transparent bridging supported on-chip,

with configurable aging time and frame lifetime control.

• Flow control supported for both full duplex and half duplex operation: supports

IEEE 802.3x PAUSE frame flow control in full-duplex mode, and supports user-enabled

backpressure flow control in half-duplex mode with configurable buffer

thresholds and limits.

• Configuration, management, MIB statistics and diagnostics available in-band or

out-of-band.

• Maintains and collects per-port and per-host statistics at wire rates, allowing a

network switch comprised of PM3351 and PM3350 chips to implement RMON

statistics (EtherStats and HostStats) using supplied on-chip firmware.

• Interfaces directly to industry-standard 100 Mbit/s transceivers with no glue logic

via the built-in Medium Independent Interface (MII) port with full support for the

autonegotiation function implemented by the PHY devices.

• Fully static CMOS operation at 50 MHz clock rates.

• 3.3 Volt core, 5 Volt compatible I/O

• 208 pin PQFP package.