Typical Applications (Continued)
the cable. A voltage divider is necessary to scale the voltage
to the required level at the input of the CLC014. This resistor
network also provides the correct impedance match for
twisted pair.
For Category 5 UTP, the approximate AEC voltage per
length is 3.75 mV/m (see Block Description ). The CLC006
provides a trim adjust for fine tuning the output signal with
the resistor R. Refer to the CLC006/007 datasheet for tuning
directions.
DS100056-33
FIGURE 13. Twisted Pair Equalization
DS100056-34
FIGURE 14. Before and After Equalization at 622 Mbps
Through 50 Meters of Category 5 UTP
End of cable before
equalization
Tektronix
Can substitute a
75Ω resistor
CSA907T
Display
Output
CSA907T
1.3Vpp
Pattern
223-1
Vcc
CLK
Data
1N4148
Vertical scale: 200mV/div
1ns/div
800mVpp
Adaptive Cable
75Ω
Coax Cable
75Ω
0.1µF
75Ω
Equalizer
0.1µ
43.3Ω
100Ω
DI
DO
DO
100Ω
End of cable after
equalization
DI
86Ω
0.1µ
37.5Ω
75Ω
CD
MUTE
50 – 75Ω
minimum loss pad
AEC+
AEC-
270Mbps data through 300m
of Belden 8281 coax cable
0.1µ
CAEC
Vertical scale: 200mV/div
1ns/div
CLC014
DS100056-35
FIGURE 15. Typical Measurement Setup
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