XRT83SL314ES Exar, XRT83SL314ES Datasheet - Page 26

• Manufacturer Part Number: XRT83SL314ES
• Description: LIN Transceivers 14 CHT1/E1 LIUSH
• Manufacturer: Exar

Specifications of XRT83SL314ES

• Product Category: LIN Transceivers
• Rohs: yes

XRT83SL314
REV. 1.0.1
In T1 mode, RLOS is declared if an incoming signal has no transitions over a period of 175 +/-75 contiguous
pulse intervals. However, the XRT83SL314 LIU has a built in analog RLOS so that the user can be notified
when the amplitude of the incoming signal has been attenuated -9dB below the equalizer gain setting. For
example: In T1 or E1 short haul mode, the equalizer gain setting is 15dB. Once the input reaches an
amplitude of -24dB below nominal, the LIU will declare RLOS. The RLOS circuitry clears when the input
reaches +3dB relative to where it was declared. This +3dB value is a pre-determined hysteresis so that
transients will not cause the RLOS to clear. In E1 mode, RLOS is declared if an incoming signal has no
transitions for N consecutive pulse intervals, where 10≤N≤255. According to G.775, no transitions in E1 mode
is defined between -9dB and -35dB below nominal. Figure 14 is a simplified block diagram of the analog
RLOS function. Table 6 summarizes the analog RLOS values for the different equalizer gain settings.
F
N
By enabling the extended loss of signal by programming the appropriate channel register, the digital RLOS is
extended to count 4,096 consecutive zeros before declaring RLOS in T1 and E1 mode. By default, EXLOS is
disabled and RLOS operates in normal mode.
The XRT83SL314 adheres to the ITU-T G.775 specification for an all ones pattern. The alarm indication signal
is set to "1" if an all ones pattern (at least 99.9% ones density) is present for T, where T is 3ms to 75ms in T1
mode. AIS will clear when the ones density is not met within the same time period T. In E1 mode, the AIS is
set to "1" if the incoming signal has 2 or less zeros in a 512-bit window. AIS will clear when the incoming signal
has 3 or more zeros in the 512-bit window.
2.6.3.2
2.6.3.3
IGURE
OTE
: For programming the equalizer gain setting on a per channel basis, see the microprocessor register map for details.
29dB (Monitoring Gain Mode)
15dB (Short Haul Mode)
14. A
G
NALOG
AIN
EXLOS (Extended Loss of Signal)
AIS (Alarm Indication Signal)
S
ETTING
T
R
ABLE
ECEIVE
+3dB
6: A
L
NALOG
OS OF
-9dB
S
RLOS D
IGNAL FOR
14-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT
ECLARE
+3dB
T1/E1/J1
D
-24dB
-38dB
ECLARE
23
/C
-9dB
LEAR
(T
Normalized up to EQC[4:0] Setting
Normalized up to EQC[4:0] Setting
Clear LOS
Declare LOS
Declare LOS
Clear LOS
YPICAL
V
ALUES
)
FOR
T1/E1
C
-21dB
-35dB
LEAR
xr