XRT7295AT Datasheet, PDF (5/18 Pages) Exar Corporation – DS3/Sonet STS-1 Integrated Line Receiver

XRT7295AT
System A
XR-T7296
Transmitter
0-450 ft.
0-450 ft.
System B
Cross
Connect
Frame
DSX-3
or STSX-1
Type 728A
Coaxial Cable
XRT7295AT
Receiver
Figure 2. Application Diagram
SYSTEM DESCRIPTION
Receive Path Configurations
In the receive signal path (see Figure 1), the internal
equalizer can be included by setting REQB = 0 or
bypassed by setting REQB = 1. The equalizer bypass
option allows easy interfacing of the XRT7295AT device
into systems already containing external equalizers.
Figure 3 illustrates the receive path options.
In Case 1 of Figure 3, the signal from the DSX-3
cross-connect feeds directly into R_IN. In this mode, the
user should set REQB = 0, engaging the equalizer in the
data path.
In Case 2 of Figure 3, external line build-out (LBO) and
equalizer networks precede the XRT7295AT device. In
this mode, the signal at R_IN is already equalized, and the
on-chip filters should be bypassed by setting REQB=1.
In applications where the XRT7295AT device is used to
monitor DS3 transmitter outputs directly, the receive
equalizer should be bypassed.
Maximum input amplitude under all conditions is 850mV
pk.
Rev.1.20
5