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

100

Ω

37.5

Ω

0.1

µ

MUTE

DI

DI

CD

DO

DO

AEC+

AEC-

100

Ω

75

Ω

CLC014

Adaptive Cable

Equalizer

75

Ω

Coax Cable

0.1

µ

75

Ω

75

Ω

1N4148

0.1

µ

0.1

µF

43.3

Ω

86

Ω

50 – 75

Ω

minimum loss pad

270Mbps data through 300m

of Belden 8281 coax cable

1ns/div

Can substitute a

75

Ω resistor

Vertical scale: 200mV/div

End of cable before

equalization

1ns/div

Vertical scale: 200mV/div

End of cable after

equalization

Display

CSA907T

Pattern

2

Tektronix

Data

CLK

Output

CSA907T

DS100056-35

FIGURE 15. Typical Measurement Setup

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