1
Micrel Semiconductor
TEL:
1.800.401.9572
FAX:
1.408.474.0159
HTTP://
www.micrel.com
KS8993 Product Brief
Revision 1.0
3-Port 10/100 Switch with Transceivers and
Frame Buffers
Micrel's KS8993 is the world's first integrated three-
port 10/100 Fast Ethernet switch with enhanced QoS. This
device integrates three 10BASET/100BASETX
transceivers, three MAC (Media Access Control) units
with high-speed layer 2 switch and 64k Byte embedded
frame buffer.
The KS8993 runs in two modes. The first mode is a
three-port integrated switch and the second is as a three-
port switch with the third port decoupled from the
physical port. In this mode access to the third MAC is
provided using a reverse or forward MII (Media
Independent Interface) such that an external MAC can
be directly connected to the KS8993. This interface also
supports the 7-wire (serial network inteface) as used by
some routing devices.
Block Diagram
Useful configurations include a stand alone three-
port switch as well as a two-port switch with a routing
element connected to the extra MII port. The additional
port is also useful for public network interfacing.
The KS8993 enables QoS using VLAN and 802.1p
priority queuing and 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 KS8993 supports 10BaseT,
100BaseTX and 100BaseFX as specified by the IEEE
802.3 committee.
Micrel's Patented Mixed Signal Technology
Physical signal transmission and reception are
enhanced through use of patented mixed signal circuitry
that makes the design more efficient and allows for lower
power consumption and smaller chip die size.
Micrel Semiconductor
TEL:
1.800.401.9572
FAX:
1.408.474.0159
HTTP://
www.micrel.com
2
System Level Applications
The KS8993 can be configured to fit either in a three
port 10/100 application or as a two port 10/100 network
interface with an extra MII port. This MII port can be
connected to an external processor and used for routing
purposes or public network access. The major benefits
of using the KS8993 are the lower power consumption,
unmanaged operation, flexible configuration and built in
frame buffering.
Typical Enterprise IP phone application using
KS8993 switch to connect one port to phone and other
port to PC.
STOCK NO. M-1004
Features
World's first 3-port 10/100 integrated switch with
physical layer transceivers
64kB SRAM on chip for frame buffering
1.0Gbps high performance memory bandwidth
Low power dissipation: 300mA (0.75W) including
physical transmit drivers
Supports port-based VLAN
Supports 802.1p-based priority or port-based priority.
Support for UTP or fiber installations
Indicators for link, activity, full/half-duplex and speed
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
On-chip integrated address look-up engine, supports
1K absolute MAC addresses
Automatic address learning, address aging and address
migration
Full-duplex IEEE 802.3x flow control
Half-duplex back pressure flow control
Optional external MAC interface (MII or SNI) for router
applications
10BaseT, 100BaseTX and 100BaseFX modes of
operation
Single 2.5V power supply
Available in 128-pin PQFP package
Contact Micrel Semiconductor
Location
Address
Telephone
Fax
Corporate HQ
1849 Fortune Drive
San Jose, CA 95131 USA
+1 (408) 944-0800
+1-408-944-0970
Eastern USA
93 Branch Street
Medford, NJ 08055 USA
+1 (609) 654-0078
+1 (609) 546-0989
Southeast USA
8105 Bluffridge Drive
Raleigh, NC 27615 USA
+1 (919) 870-7650
+1 (919) 870-7651
Central USA
722 S. Denton Tap Suite 130
Coppell, TX 75019 USA
+1 (972) 393-2533
+1 (972) 393-2540
Western USA
2180 Fortune Drive
San Jose, CA 95131 USA
+1 (408) 944-0800
+1-408-944-0970
Northwest USA
401 NE Ravenna Blvd. Box 152
Seattle, WA 98115 USA
+1 (206) 526-7299
+1 (206) 526-8829
Southwest USA
7545 Irvine Center Dr. Suite 200
Irvine, CA 92618 USA
+1 (949) 623-8343
+1 (949) 623-8305
Korea
4F, KTB Building, 826-14, Yeoksam-dong, Kangnam-ku
Seoul 135-080 Korea
+82 (2) 3466-3000
+82 (2) 3466-2999
Taiwan
7F-6, No. 237, Sec. 2, Fu-Hsing South Road
Taipei, Taiwan, R.O.C.
+886 (2) 2705-4976
+886 (2) 2705-4977
China
12A, XingHao City Garden
Shenzhen, P.R. China
+86 (755) 2693-4601
Japan
1-16-15 Dogenzaka, Shibuyaku
Tokyo 150-0043 Japan
+81 (3) 5428-0871
+81 (3) 5428-0872
Europe
1st Floor, 3 Lockside Place, Mill Lane
Newbury, Berks RG14 5QS UK
+44 1635 524455
+44 1635 524466
Western Europe
10, avenue du Quebec, Villebon BP116
Courtaboeuf Cedex 91944 France
+33 (0) 1 6092 4189
+33 (0) 6 0868 4489
PDF 
ZIP