KS8997 Micrel Inc, KS8997 Datasheet - Page 16

• Manufacturer Part Number: KS8997
• Description: IC SWITCH 10/100 8PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8997

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Fiber Support: No
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII
• Power Supply Type: Analog/Digital
• Package Type: PQFP
• Data Rate (typ): 10/100Mbps
• Vlan Support: Yes
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 128
• Mounting: Surface Mount
• Jtag Support: No
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

KS8997
Auto-Negotiation
The KS8997 conforms to the auto-negotiation protocol as described by the 802.3 committee. Auto-negotiation allows UTP
(Unshielded Twisted Pair) link partners to select the best common mode of operation. In auto-negotiation the link partners
advertise capabilities across the link to each other. If auto-negotiation is not supported or the link partner to the KS8997 is forced
to bypass auto-negotiation, then the mode is set by observing the signal at the receiver. This is known as parallel mode because
while the transmitter is sending auto-negotiation advertisements, the receiver is listening for advertisements or a fixed signal
protocol.
The flow for the link set up is depicted below. Note that the KS8997 only supports auto-negotiation and not forced modes.
KS8997
Start Auto Negotiation
Force Link Setting
and Set Link Mode
Auto-Negotiation
Bypass
Yes
Figure 1. Auto-Negotiation
Auto-Negotiation
Attempt
No
16
Listen for 100BaseTX
Link Mode Set ?
Link Mode Set
Operation
Join Flow
Parallel
Idles
Yes
Listen for 10BaseT
Link Pulses
No
August 2003
Micrel