ADSL Router Controller

General Description

Realtek offers an integrated SoC featuring a RISC, an ADSL Discrete MultiTone (DMT) datapump, a hardware ATM Segmentation and Reassembly (SAR), a 10/100Mbps IEEE 802.3 compatible MAC with Ethernet transceiver, a USB 1.1 transceiver, and a PCI bridge interface. Mated with the Realtek ADSL Analog Front End, it provides a low cost integrated solution for ADSL CPE modem, router, or gateway.

Realtek ADSL solution encompasses high-performance DSP technologies, optimized mix-signal designs and an efficient system architecture to provide a seamless WAN to LAN router controller. The embedded RISC network processor achieves a 150MHz clock rate in a five-stage pipeline to support layer 2, 3, and other upper layer applications.

The DMT engine supports 32kbps ~ 1024kbps upstream, and 32kbps ~ 12Mbps downstream channel throughput and is compatible with:

  • ANSI TI.413 Issue 2
  • ITU-T G.992.1 (G.dmt) Annexes A and B
  • G.992.2 (G.lite) Annexes A and B

The Fast Ethernet interface offers high-speed transmission over CAT.5 UTP cable. Ethernet functions such as crossover detection & auto-correction and polarity correction are implemented to provide robust transmission and reception capability at high speeds. An option exists to switch the Ethernet MAC to an MII interface, extending the application to a multiport ADSL gateway with an additional 5 port 10/100Mbps Ethernet switch controller (e.g. Realtek RTL8305SB or RTL8305SC).

The USB 1.1 transceiver achieves data throughput up to 12Mbps. The SoC also features a host PCI bridge capable of addressing one external PCI device such as IEEE 802.11a/b/g WiFi controller (e.g. Realtek RTL8185L).


  • Two-chip ADSL CPE solution
  • Field proven DMT datapump is compatible with ANSI TI.413 Issue 2, ITU-T G.992.1 (G.dmt) and G.992.2 (G.lite). Supports Annexes A & B
  • 150MHz embedded RISC
  • Integrated hardware ATM SAR with up to 16 distinct VCC's, ATM AAL5 support for CBR, UBR, F4/F5 OAM cell, HEC, CRC, Ingress IP/TCP/UDP checksum offload, error packet filtering
  • Integrated 10/100 Base-TX Ethernet MAC and Transceiver supporting crossover detection and auto-correction and polarity correction
  • Integrated USB1.1 Transceiver supporting IP/TCP/UDP checksum offload and bridging to Ethernet interface
  • On-chip PCI interface enables WLAN support
  • DSL auto-configuration TR-037 compatible
  • 16/32 bit wide SDRAM support
  • 8/16 bit wide FLASH support
  • Dying Gasp support
  • JTAG support


  • ADSL multiport router
  • ADSL single-port router/modem
  • ADSL pure bridge
  • Wireless ADSL router