The KS8999 contains eight 10/100 physical layer transceivers, nine MAC (Media Access Control) units with an integrated layer 2 switch.

The device runs in two modes. The first mode is an eight port integrated switch and the second is as a nine port switch with the ninth port available through an MII (Media Independent Interface).

Useful configurations include a stand alone eight port switch as well as a eight port switch with a routing element connected to the extra MII port. The additional port is also useful for a public network interfacing. The KS8999 is designed to reside in an unmanaged design not requiring processor intervention. This is achieved through I/O strapping or EEPROM programming at system reset time.

On the media side, the KS8999 supports 10BaseT, 100BaseTX and 100BaseFX as specified by the IEEE 802.3 committee. Physical signal transmission and reception are enhanced through use of analog circuitry that makes the design more efficient and allows for lower power consumption and smaller chip die size.

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  9 port (8+1) 10/100 integrated switch with eight physical layer transceivers and one MII/SNI interface

  Advanced Ethernet Switch with internal frame buffer

  128K Byte of SRAM on chip for frame buffering

  2.0Gbps high performance memory bandwidth

  Wire speed reception and transmission

  Integrated address look-up engine, supports 1K absolute MAC addresses

  Automatic address learning, address aging and address migration

  Advanced Switch Features

  Supports 802.1p priority and port based priority

  Supports port based VLAN

  Supports 1536 byte frame for VLAN tag

  Supports DiffServ priority, 802.1p based priority or port based priority of broadcast storm protection

  Proven transceiver technology for UTP and fiber operation

  10BaseT, 100BaseTX and 100BaseFX modes of operation

  Supports for UTP or fiber on all 8-ports

  Indicators for link, activity, full/half-duplex and speed

  Hardware based 10/100, full/half, flow control and auto-negotiation

  Individual port forced modes (full duplex, 100BaseTX) when auto-negotiation is disabled

  Full-duplex IEEE 802.3x flow control

  Half-duplex back pressure flow control

  Supports MDI/MDI-X auto crossover

  External MAC interface (MII or 7-wire) for router applications

  Unmanaged operation via strapping or EEPROM at system reset time (see Reset Reference Circuit section)

  Comprehensive LED support

  Single 2.0V power supply with options for 2.5V and 3.3V I/O

  900 mA (1.80W) including physical transmit drivers

  Supports both commercial and industrial temperature

  Commercial temperature range: 0°C to +70°C (KS8999)

  Industrial temperature range: –40°C to +85°C (KS8999I)

  Supports lead free products:

  Commercial temperature range: 0°C to +70°C (KSZ8999)

  Industrial temperature range: –40°C to +85°C (KSZ8999I)