XRT75R12 Datasheet, PDF (43/89 Pages) Exar Corporation – TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR

PRELIMINARY
TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR
XRT75R12
REV. P1.0.2
TABLE 11: JITTER TRANSFER PASS MASKS
RATE
(KBITS)
MASK
F1
F2
F3
F4
A1(dB)
A2(dB)
(HZ)
(HZ)
(HZ)
(KHZ)
G.823
100
300
34368
ETSI-TBR-24
3K
800K
0.5
-19.5
44736
GR-499, Cat I
10
10k
-
15k
0.1
-
GR-499, Cat II
10
56.6k
-
300k
0.1
-
GR-253 CORE
10
40
-
15k
0.1
-
51840
GR-253 CORE
10
40k
-
400k
0.1
-
The jitter attenuator within the XRT75R12 meets the latest jitter attenuation specifications and/or jitter transfer
characteristics as shown in the Figure 28.
FIGURE 28. JITTER TRANSFER REQUIREMENTS AND JITTER ATTENUATOR PERFORMANCE
A1
A2
F1
F2
F3
F4
JITTE R FR E Q U E N C Y (kH z)
5.3.1 JITTER GENERATION
Jitter Generation is defined as the process whereby jitter appears at the output port of the digital equipment in
the absence of applied input jitter. Jitter Generation is measured by sending jitter free data to the clock and
data recovery circuit and measuring the amount of jitter on the output clock or the re-timed data. Since this is
essentially a noise measurement, it requires a definition of bandwidth to be meaningful. The bandwidth is set
according to the data rate. In general, the jitter is measured over a band of frequencies.
40