AN983 ETC [List of Unclassifed Manufacturers], AN983 Datasheet - Page 89

• Manufacturer Part Number: AN983
• Description: PCI/miniPCI-to-Ethernet LAN Controller
• Manufacturer: ETC [List of Unclassifed Manufacturers]

12. LAYOUT GUIDE
Layout Guide Revision History:
Revision Date
October, 2000
12.1 PLACEMENT
12.2 TRACE ROUTING
Rev. 1.8
1). Tx+/- Rx+/- differential pairs
2). PCB edge.
3). Transformer
4). Any other high frequency item and associated traces.
1). Tx+/- and Rx+/- trace avoid right angle signal trace, suggest round angle >90
2). Trace width must be wide that should be 2X layout program minimum request or wide than
3). Signal trace length between Tx+/- differential pairs should be cross to equal length the total
4). Make Tx and Rx trace route at the same signal plane and had better not using bias.
5). Every differential pairs as cross as possible, but no less then 8 miles and the space should
Keep the distance as short as possible between Centaur-P and
transformer, as well as transformer and RJ45.
Make crystal device cross to Centaur-P pin x1 x2, and away from the
following item:
Tx pull high resister needs to close to chip and Rx receiving termination
resister and cap need to close to transformer.
De-couple cap should be placed as close to chip as possible. The traces
should be short.
Use ample dc-coupling and bulk capacitors to minimize noise.
Use X7R ceramic capacitor for better capacitive characteristics over
temperature.
Arrangement Tx and Rx trace
8 miles.
should no long to 2 cm.same require apply to Rx+/-.
be almost equal.
Revision
1.0b
(REV.1.0B)
AN983B
Description
Add Item 2-d to reduce receive CRC error.
www.admtek.com.tw
ADMtek Inc.
PCI/miPCI Fast Ethernet Controller with integrated PHY
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