MICREL KS8842

KS8842-16MQL
KS8842-32MQL
www.micrel.com
Product Brief
2-Port Ethernet Switch
with Non-PCI Interface
Description
Benefits
The KS8842M is the industry’s first fully managed 2-port
switch with a non-PCI CPU interface. The KS8842 is a
proven, 4th generation, integrated Layer 2 switch that is
compliant to the IEEE 802.3u standard.
The KS8842M can also be configured as a low-latency
repeater to allow for ‘cut thru’ in latency critical Embedded
or Industrial Ethernet applications. For industrial automation applications in the repeater mode, the KS8842M runs
in half-duplex mode regardless of the application.
The KS8842M offers an extensive feature set that includes
tag/port-based VLAN, QoS priority management, MAC
filtering function, MIB counters, and CPU control/data
interfaces to effectively address both current and emerging Fast Ethernet applications.
The KS8842 contains two 10/100 transceivers with patented mixed-signal low-power technology, two media access control (MAC) units and a direct memory access
(DMA) channel, a high-speed non-blocking switch fabric,
a dedicated 1K entry forwarding table, and an on-chip
frame buffer memory.
Offers all of the features of an integrated Layer 2
managed switch plus:
• Fully compliant to the IEEE 802.3u standard
• Repeater mode capabilities to allow for ‘cut-thru’ in
latency critical Industrial Ethernet or Embedded
Ethernet applications
• MAC filtering function to filter unicast packets
• Dynamic buffer memory scheme
– Essential for applications such as Video over IP
where image jitter is unacceptable
• 2-Port switch with flexible 8/16/32 bit generic host
processor interface
• Micrel LinkMDTM cable diagnostic capabilities to
determine cable length, diagnose faulty cables, and
determine distance to fault
• HP Auto MDI-X crossover with disable and enable
option
• Industrial Temperature support: –40oC to +85oC
available from Q4
• Four priority queues to handle voice, video, data,
and control packets
Block Diagram
Applications
1K Look-Up
Engine
10/100
T/TX
PHY 1
10/100
MAC 1
HP Auto
MDI/MDI-X
10/100
T/TX
PHY 2
10/100
MAC 2
DMA
Channel
Embedded
Processor Interface
Non-PCI
CPU
Bus Interface Unit
8/16/32 Bit
Generic Host Interface
FIFO, Flow Control, VLAN Tagging, Priority
HP Auto
MDI/MDI-X
Queue
Management
Buffer
Management
• Industrial applications for daisy chaining
multiple devices
• Industrial control in latency critical
applications
• Port redundancy and port monitoring
• Security cameras
• VoIP phone and ATA adaptors
Frame
Buffers
MIB
Counters
Control
Registers
EEPROM
Interface
EEPROM I/F
P1 LED[3:0]
P2 LED[3:0]
LED
Drivers
Note: For an MII/RMII, I2C or SPI interface, use the KS8883ML.
Micrel Semiconductor
TEL: 1.408.944.0800
FAX: 1.408.474.1000 HTTP:// www.micrel.com
LinkMD is a trademark of Micrel, Inc.