KS8999
Micrel
KS8999
Integrated 9-Port 10/100 Switch with PHY and Frame Buffer
Rev. 1.14
General Description
The KS8999 contains eight 10/100 physical layer transceiv-
ers, nine MAC (Media Access Control) units with an inte-
grated 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 consump-
tion and smaller chip die size.
Data sheets and support documentation can be found on
Micrel鈥檚 web site at www.micrel.com.
Functional Diagram
Look Up
Engine
(1K Entries)
Queue Priority
Management
Buffer
Management
SRAM
Buffers
FIFO, Flow Control, VLAN and Priority
M
A
C
1
M
A
C
2
M
A
C
3
M
A
C
4
M
A
C
5
M
A
C
6
M
A
C
7
M
A
C
8
M
A
C
9
P
H
Y
1
P
H
Y
2
P
H
Y
3
P
H
Y
4
P
H
Y
5
P
H
Y
6
P
H
Y
7
P
H
Y
8
MII /
SNI
(exclusive)
External
Interface
M
I
I
MRXD[3:0]
MRXDV
MCOL
MCRS
MTXD[3:0]
MTXEN
MTXER
MTXC
MRXC
MRXD[0]
MRXDV
MCOL
EEPROM /
Processor
Interface
SCL
SDA
LED
and
Programming
Interface
LED[1][3:0]
LED[2][3:0]
LED[3][3:0]
LED[4][3:0]
LED[5][3:0]
LED[6][3:0]
LED[7][3:0]
LED[8][3:0]
LED[9][3:0]
S
N
I
MTXD[0]
MTXEN
MTXC
MRXC
Micrel, Inc. 鈥?2180 Fortune Drive 鈥?San Jose, CA 95131 鈥?USA 鈥?tel + 1 (408) 944-0800 鈥?fax + 1 (408) 474-1000 鈥?http://www.micrel.com
January 2005
1
KS8999