KS8995X
Micrel
KS8995X
Integrated 5-Port 10/100 QoS Switch
Rev. 1.13
General Description
The KS8995X is a highly integrated Layer-2 QoS (Quality of
Service) switch with optimized BOM (Bill of Materials) cost for
low port count, cost-sensitive 10/100Mbps switch systems. It
also provides an extensive feature set including three differ-
ent QoS priority schemes, a dual MII interface for BOM cost
reduction, rate limiting to offload CPU tasks, software and
hardware power-down, a MDC/MDIO control interface and
port mirroring/monitoring to effectively address both current
and emerging Fast Ethernet applications.
The KS8995X contains five 10/100 transceivers with pat-
ented mixed-signal low-power technology, five MAC (Media
Access Control) units, a high-speed non-blocking switch
fabric, a dedicated address lookup engine, and an on-chip
frame buffer memory.
All PHY units support 10BaseT and 100BaseTX. In addition,
two of the PHY units support 100BaseFX (Ports 4 and 5).
All support documentation can be found on Micrel’s web site
at www.micrel.com.
Features
• Integrated switch with five MACs and five Fast Ethernet
transceivers fully compliant to IEEE 802.3u standard
• Shared memory based switch fabric with fully non-
blocking configuration
• 10BaseT, 100BaseTX and 100BaseFX modes (FX in
Ports 4 and 5)
• Dual MII configuration: MII-Switch (MAC or PHY mode
MII) and MII-P5 (PHY mode MII)
• VLAN ID tag/untag options, per-port basis
• Enable/disable option for huge frame size up to 1916
bytes per frame
• Broadcast storm protection with percent control – global
and per-port basis
• Optimization for fiber-to-copper media conversion
• Full-chip hardware power-down support (register
configuration not saved)
• Per-port-based software power-save on PHY (idle link
detection, register configuration preserved)
• QoS/CoS packets prioritization supports: per port,
802.1p and DiffServ based
Functional Diagram
Auto
MDI/MDIX
Auto
MDI/MDIX
Auto
MDI/MDIX
Auto
MDI/MDIX
Auto
MDI/MDIX
MII-P5
MDC, MDI/O
MII-SW or SNI
LED0[5:1]
LED1[5:1]
LED2[5:1]
10/100
T/Tx 1
10/100
T/Tx 2
10/100
T/Tx 3
10/100
T/Tx/Fx 4
10/100
T/Tx/Fx 5
10/100
MAC 1
FIFO, Flow Control, VLAN Tagging, Priority
1K look-up
Engine
Queue
Mgmnt
Buffer
Mgmnt
Frame
Buffers
10/100
MAC 2
10/100
MAC 3
10/100
MAC 4
10/100
MAC 5
SNI
LED I/F
Control
Registers
EEPROM
I/F
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
December 2003
1
M9999-120403
MICREL [ MICREL SEMICONDUCTOR ]
