VSC8641XKO Vitesse Semiconductor Corp, VSC8641XKO Datasheet - Page 36

• Manufacturer Part Number: VSC8641XKO
• Description: IC PHY 10/100/1000 100-LQFP
• Manufacturer: Vitesse Semiconductor Corp
• Type: PHY Transceiverr

Specifications of VSC8641XKO

• Number Of Drivers/receivers: 1/1
• Protocol: Gigabit Ethernet
• Voltage - Supply: 2.5V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 100-LQFP
• Case: TQFP
• Dc: 07+
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 907-1031

3.13.5
Figure 15.
3.13.6
Revision 4.3
August 2009
Connector Loopback
The connector loopback testing feature allows for the twisted pair interface to be looped
back externally. When using this feature, the PHY must be connected to a loopback
connector or a loopback cable. Pair A should be connected to pair B and pair C to
pair D, as shown in the following illustration. The connector loopback feature functions
at all available interface speeds.
Connector Loopback
When using the connector loopback testing feature, the device auto-negotiation, speed,
and duplex configuration is set using device registers 0, 4, and 9. For 1000BASE-T
connector loopback, only the following additional writes are required. Execute the
additional writes in the following order:
1. Enable the 1000BASE-T connector loopback. Set register bit 24.0 to 1.
2. Disable the pair swap correction. Set register bit 18.5 to 1.
VeriPHY Cable Diagnostics
The VSC8641 device includes a comprehensive suite of cable diagnostic functions that
are available using SMI reads and writes. These functions enable a variety of cable
operating conditions and status to be accessed and checked. The VeriPHY suite has the
ability to identify the cable length and operating conditions and to isolate a variety of
common faults that can occur on the Cat5 twisted pair cabling.
For more information, see the PHY API Software and Programmers Guide on the Vitesse
Web site at www.vitesse.com.
Note If a link is established on the twisted pair interface in 1000BASE-T mode,
VeriPHY can run without disrupting the link or any data transfer. However, if a link is
established in 100BASE-TX or 10BASE-T, VeriPHY causes the link to drop while the
diagnostics are running. After the diagnostics are finished, the link is then re-
established.
The following diagnostic functions are part of the VeriPHY suite:
•
•
•
Coupling Between Cable Pairs
crosstalk resulting from an incorrect wire map can cause error conditions, such as
Cat5
Detection of coupling between cable pairs
Detection of cable pair termination
Determination of cable length
A
B
C
D
SimpliPHY
RXD
TXD
Shorted wires, improper termination, or high
MAC
Functional Descriptions
VSC8641 Datasheet
Page 36