XRT83L314 Datasheet, PDF (31/84 Pages) Exar Corporation – 14-CHANNEL T1/E1/J1 LONG-HAUL/SHORT-HAUL LINE INTERFACE UNIT

XRT83L314
14-CHANNEL T1/E1/J1 LONG-HAUL/SHORT-HAUL LINE INTERFACE UNIT
REV. 1.0.0
TABLE 7: TIMING SPECIFICATIONS FOR TCLK/TPOS/TNEG
PARAMETER
SYMBOL
MIN
TCLK Duty Cycle
T_CDU
30
Transmit Data Setup Time
T_SU
50
Transmit Data Hold Time
T_HO
30
TCLK Rise Time (10% to 90%)
TCLK_R
-
TCLK Fall Time (90% to 10%)
TCLK_F
-
TYP
MAX
50
70
-
-
-
-
-
40
-
40
UNITS
%
ns
ns
ns
ns
NOTE: VDD=3.3V ±5%, T_A=25°C, Unless Otherwise Specified
3.2 HDB3/B8ZS Encoder
In single rail mode, the LIU can encode the TPOS input signal to AMI or HDB3/B8ZS data. In E1 mode and
HDB3 encoding selected, any sequence with four or more consecutive zeros in the input will be replaced with
000V or B00V, where "B" indicates a pulse conforming to the bipolar rule and "V" representing a pulse violating
the rule. An example of HDB3 encoding is shown in Table 8. In T1 mode and B8ZS encoding selected, an
input data sequence with eight or more consecutive zeros will be replaced using the B8ZS encoding rule. An
example with Bipolar with 8 Zero Substitution is shown in Table 9.
TABLE 8: EXAMPLES OF HDB3 ENCODING
NUMBER OF PULSES BEFORE
NEXT 4 ZEROS
Input
0000
HDB3 (Case 1)
Odd
000V
HDB3 (Case 2)
Even
B00V
TABLE 9: EXAMPLES OF B8ZS ENCODING
CASE 1
PRECEDING PULSE
NEXT 8 BITS
Input
+
00000000
B8ZS
000VB0VB
AMI Output
+
000+-0-+
Case 2
Input
-
00000000
B8ZS
000VB0VB
AMI Output
-
000-+0+-
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