Category 5 UTP has a characteristic impedance of approxi-

mately 100

Ω. The CLC006 in Figure 13 is used to drive the

twisted pair AC-coupled with a series 0.1 µF capacitor and a

50

Ω resistor in each differential output. The CLC014 Adap-

tive Equalizer requires 800 mV

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.

10005633

FIGURE 13. Twisted Pair Equalization

10005634

FIGURE 14. Before and After Equalization at 622 Mbps

Through 50 Meters of Category 5 UTP

10005635

FIGURE 15. Typical Measurement Setup

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