KSZ9031 Series Ethernet Transceiver

By Microchip Technology 93

KSZ9031 Series Ethernet Transceiver

Microchip's KSZ9031 series Ethernet transceivers are a completely integrated, triple-speed (10Base-T/100Base-TX/1000Base-T) Ethernet physical-layer transceiver for transmission and reception of data on standard CAT-5 unshielded twisted pair (UTP) cable. The reduced board cost simplifies board layout by using on-chip termination resistors for the four differential pairs, and by integrating an LDO controller to drive a low-cost MOSFET to supply the 1.2 V core. The KSZ9031RNX and KSZ9031MNX offer diagnostic features to facilitate system bring-up and debugging in production testing and deployment. Parametric NAND tree support enables fault detection between KSZ9031 I/Os and the board. The LinkMD® TDR-based cable diagnostic identifies faulty copper cabling. Remote and local loopback functions verify analog and digital data paths.

The KSZ9031RNX provides the Reduced Gigabit Media Independent Interface (RGMII) for direct connection to RGMII MACs in Gigabit Ethernet processors and switches, enabling data transfer at 10/100/1000 Mbps. The KSZ9031RNX is available in a 48-pin, lead-free QFN package.

The KSZ9031MNX offers the industry-standard GMII/MII (Gigabit Media Independent Interface/Media Independent Interface) for connection to GMII/MII MACs in Gigabit Ethernet processors and switches for data transfer at 1000 Mbps or 10/100 Mbps. The KSZ9031MNX is available in a 64-pin, lead-free QFN package.


  • Single-chip, 10/100/1000 Mbps IEEE 802.3-compliant Ethernet transceiver
  • Auto-negotiation to automatically select the highest link-up speed (10/100/1000 Mbps) and duplex (half/full)
  • On-chip termination resistors for the differential pairs
  • On-chip LOD controller to support single 3.3 V supply operation, requires only one external FET to generate 1.2 V for the core
  • Jumbo-frame support up to 16 KB
  • 125 MHz reference clock output
  • Energy-detect power-down mode for reduced power consumption when the cable is not attached
  • Energy Efficient Ethernet (EEE) support with low-power idle (LDI) mode and clock stoppage for 100Base-TX/1000Base-T, and transmit amplitude reduction with 10Base-Te option
  • Laser/network printers
  • Network attached storage (NAS)
  • Network servers
  • Gigabit LAN on motherboards (GLOM)
  • Broadband gateways
  • Gigabit SOHO/SMB routers
  • IPTV
  • IP set-top boxes
  • Game consoles
  • Triple-play (data, voice, video) media centers
  • Media converters