xrt83l30 Exar Corporation, xrt83l30 Datasheet - Page 23

• Manufacturer Part Number: xrt83l30
• Description: Xrt83l30 -single-channel T1/e1/j1 Long-haul, Short-haul Line Interface Unit
• Manufacturer: Exar Corporation

F
F
REV. 1.0.1
Once the T1/E1 input signal has been normalized to 0dB by adding the maximum gain (+29dB), the receiver
will declare RLOS if the signal is attenuated by an additional -9dB. The total cable loss at RLOS declaration is
typically -38dB (-29dB + -9dB). A 3dB hysteresis was designed so that transients will not trigger the RLOS to
clear. Therefore, the RLOS will typically clear at a total flat loss of -35dB. See
Setting the Receiver Input to -36dB T1/E1 Long Haul Mode
By setting the receiver input to -36dB T1/E1 long haul mode, the equalizer will detect the incoming amplitude
and make adjustments by adding gain up to a maximum of +36dB normalizing the T1 input signal. This setting
refers to cable loss (frequency), not flat loss (resistive). Once the T1/E1 input signal has been normalized to
0dB by adding the maximum gain (+36dB), the receiver will declare RLOS if the signal is attenuated by an
additional -9dB. The total cable loss at RLOS declaration is typically -45dB (-36dB + -9dB). A 3dB hysteresis
was designed so that transients will not trigger the RLOS to clear. Therefore, the RLOS will typically clear at a
total cable attenuation of -42dB. See
E1 Extended RLOS
E1: Setting the Receiver Input to Extended RLOS
By setting the receiver input to extended RLOS, the equalizer will detect the incoming amplitude and make
adjustments by adding gain up to a maximum of +43dB normalizing the E1 input signal. This setting refers to
IGURE
IGURE
7. S
8. S
IMPLIFIED
IMPLIFIED
SINGLE-CHANNEL T1/E1/J1 LH/SH TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
+3dB
+3dB
D
D
IAGRAM OF
IAGRAM OF
-9dB
-9dB
-29dB T1/E1 G
-36dB T1/E1 L
Figure 8
+3dB
+3dB
for a simplified diagram.
ONG
AIN
M
20
H
ODE AND
-9dB
-9dB
AUL
M
ODE AND
RLOS C
Clear LOS
Clear LOS
Clear LOS
Clear LOS
Declare LOS
Declare LOS
Declare LOS
Declare LOS
Norm alized up to +29dB Max
Norm alized up to +36dB Max
Norm alized up to +29dB Max
Norm alized up to +36dB Max
RLOS C
ONDITION
Figure 7
ONDITION
for a simplified diagram.
XRT83L30