KS8995 – 5 Port 10/100 Switch with PHY
Introduction
The KS8995 contains five 10/100 physical layer
transceivers, five MAC (Media Access Control) units
with an integrated layer 2 switch. The device runs in
two modes. The first mode is a five port integrated
switch and the second is as a five port switch with the
fifth port decoupled from the physical port. In this
mode access to the fifth MAC is provided using a
MII (Media Independent Interface).
Useful configurations include a stand alone five port
switch as well as a four port switch with a routing
element connected to the extra MII port. The
additional port is also useful for public network
interfacing.
The KS8995 is designed to reside in an unmanaged
design not requiring processor intervention. This is
achieved through I/O strapping at system reset time
On the media side, the KS8995 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.
Highlights
486 Mercury Drive, Sunnyvale, California 94086
5 port 10/100 Integrated Switch with Physical
Layer Transceivers
SRAM on chip for frame buffering
1.4Gbps high performance memory bandwidth
10BaseT, 100BaseTX and 100BaseFX modes of
operation
Superior analog technology for reduced power
and die size
Single 2.5 V power supply
500 mA (1.25 W) including physical transmit
drivers
128 pin PQFP package
Support for UTP or fiber installations
Indicators for link, activity, full / half duplex and
speed
Tel: (408) 735-1118
Transceiver
Physical
MAC
(1K Entries)
Look Up
1
1
Unmanaged operation via strapping at system
reset time
Hardware based 10/100, full/half, flow control
and auto negotiation
Individual port forced modes (full duplex,
100BaseTX) when auto negotiation is disabled
Wire speed reception and transmission
Integrated address Look-Up Engine, supports 1K
absolute MAC addresses
Automatic address learning, address aging and
address migration
Broadcast storm protection
Full duplex IEEE 802.3x flow control
Half duplex back pressure flow control
Comprehensive LED support
External MAC interface (MII or SNI) for router
applications
Engine
Transceiver
Fax: (408) 735-1119
Physical
MAC
2
2
Management
Queue
FIFO and Flow Control
Transceiver
Physical
MAC
3
3
Management
Transceiver
Buffer
Physical
MAC
4
4
www.kendin.com
Transceiver
Physical
MAC
5
5
SRAM
Buffers
Programming
Interface
LED
and
MII / SNI
(exclusive)
External
Interface
LED[1][3:0]
LED[2][3:0]
LED[3][3:0]
LED[4][3:0]
LED[5][3:0]
M
I
I
S
N
I
MRXD[3:0]
MRXDV
MCOL
MTXD[3:0]
MTXEN
MTXER
MII_CLK
MRXD[0]
MRXDV
MCOL
MTXD[0]
MTXEN
MII_CLK