The RTL8309N is an 8-port 10/100M Ethernet switch controller that integrates memory, eight MACs, and eight physical layer transceivers for 10Base-T and 100Base-TX operation into a single chip.
In order to accomplish diagnostics in complex network systems, the RTL8309N provides a loopback feature in each port. The RTL8309N supports several advanced QoS functions with four-level priority queues to improve multimedia or real-time networking applications, including:
- Multi-priority assignment
- Differential queue weight
- Port-based rate limitation
- Queue-based rate limitation
The RTL8309N supports 16 VLAN groups. These can be configured as port-based VLANs and/or 802.1Q tag-based VLANs. The RTL8309N also supports VLAN learning, with four Independent VLAN Learning (IVL) filtering databases.
The RTL8309N contains a 2K-entry address lookup table. A 4-way associative hash algorithm avoids hash collisions and maintains forwarding performance.
Maximum packet length can be 2048 bytes. Three types of independent storm filter are provided to filter packet storms, and an intelligent switch engine prevents Head-of-Line blocking problems.
The RTL8309N supports Energy-Efficient Ethernet mode (EEE; defined in IEEE 802.3az) to minimize system power consumption. Energy-Efficient Ethernet (EEE) supports Low Power Idle Mode. When Low Power Idle Mode is enabled, systems on both sides of the link can disable portions of the functionality and save power during periods of low link utilization.
To simplify the peripheral power circuit, the RTL8309N integrates one LDO regulator to generate 1.0V from a 3.3V input power, and needs only one external diode.