XRT83SL314 datasheet(21/83 Pages) EXAR

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XRT83SL314

14-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT

REV. 1.0.1

2.2

Equalizer Control

The main objective of the equalizer is to amplify an input attenuated signal to a pre-determined amplitude that

is acceptable to the peak detector circuit. Using feedback from the peak detector, the equalizer will gain the

input up to the maximum value specified by the equalizer control bits, in the appropriate channel register,

normalizing the signal.

Once the signal has reached the pre-determined amplitude, the signal is then

processed within the peak detector and slicer circuit. A simplified block diagram of the equalizer and peak

detector is shown in Figure 6.

FIGURE 6. SIMPLIFIED BLOCK DIAGRAM OF THE EQUALIZER AND PEAK DETECTOR

2.3

Cable Loss Indicator

The ability to monitor the cable loss attenuation of the receiver inputs is a valuable feature. The XRT83SL314

contains a per channel, read only register for cable loss indication. CLOS[5:0] is a 6-Bit binary word that

reports the value of cable loss in 1dB steps. An example of -15dB cable loss attenuation is shown in Figure 7.

FIGURE 7. SIMPLIFIED BLOCK DIAGRAM OF THE CABLE LOSS INDICATOR

Peak

Detector &

Slicer

Rx Equalizer

Control

RTIP

RRING

-15dB of Cable

Loss

Equalizer and

Peak Detector

CLOS[5:0] = 0x0Fh

(15dec = 0Fhex)

-15dB Attenuated

Signal

Read Only

XRT83SL314

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