Marvell 88E3015 Manual page 50

88E3015/88E3018
Integrated 10/100 Fast Ethernet Transceiver
Figure 13: NMOS Output Impedance (1.8V, 2.5V) Trend Lines (TBD)
80
70
60
50
40
30
20
10
0
1 2 3 4 5
Example: The automatic calibration has a 50 ohm target, but if the MII trace impedance on board was 60 ohms,
you see reflections from a scope capture taken at the destination. Refer to
see that the reflections are eliminated as in
Figure 14: Signal Reflections, using the 50 ohm Setting, 60 ohm line
Doc. No. MV-S103657-00, Rev. D
Page 50
2.5V
3.3V
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NMOS Register Value Decimal
Figure 15.
Document Classification: Proprietary Information
Figure 14. After manual calibration, you
Copyright © 2008 Marvell
January 4, 2008, Advance