SFP Copper-Cable Preemphasis Driver
VLOW_PP VHIGH_PP
PE(dB)
=
20
log
VHIGH _ PP
VLOW _PP
Figure 1. Illustration of Tx Preemphasis in dB
SIGNAL
A
SOURCE
TEST SETUP
PCBOARD (FR4)
MAX3982
6 mil
IN
OUT
6 mil
B
24AWG 100Ω TWIN-AX
SMA CONNECTORS
OSCILLOSCOPE OR
ERROR DETECTOR
1in ≤ L ≤ 10in
L ≤ 1in
L = 2in
SMA CONNECTORS
6 mil
FR4
4.0 ≤ εR ≤ 4.4
D
tan δ = 0.022
Figure 2. Test Setup. The points labeled A, B, and D are referenced for AC parameter test conditions. Deterministic jitter and eye
diagrams measured at point D.
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