XRT7295ATIWTR-F Exar Corporation, XRT7295ATIWTR-F Datasheet - Page 10

• Manufacturer Part Number: XRT7295ATIWTR-F
• Description: DS3/SONET STS-1 Line Receiver
• Manufacturer: Exar Corporation

Specifications of XRT7295ATIWTR-F

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

OUTPUT JITTER
The total jitter appearing on the RCLK output during
normal operation consists of two components. First,
some jitter appears on RCLK because of jitter on the
incoming signal. (The next section discusses the jitter
transfer characteristic, which describes the relationship
between input and output jitter.) Second, noise sources
within the XRT7295AT device and noise sources that are
coupled into the device through the power supplies and
JITTER TRANSFER CHARACTERISTIC
The jitter transfer characteristic indicates the fraction of
input jitter that reaches the RCLK output as a function of
input jitter frequency.
transfer characteristic parameters. Figure 9 also shows a
typical characteristic, with the operating conditions as
described in Table 5. Although existing standards do not
specify jitter transfer characteristic requirements, the
XRT7295AT information is provided here to assist in
evaluation of the device.
12
Rev.1.20
10
0
6
2
4
8
Figure 7. Loss Characteristic of 728A
1.0
2.0
Coaxial Cable (450 ft.)
Frequency (MHz)
5.0 10
Table 5 shows Important jitter
20
50
100
10
data pattern dependent jitter due to misequalization of the
input signal, all create jitter on RCLK. The magnitude of
this internally generated jitter is a function of the PLL
bandwidth, which in turn is a function of the input 1s
density. For higher 1s density, the amount of generated
jitter decreases. Generated jitter also depends on the
quality of the power supply bypassing networks used.
Figure 12 shows the suggested bypassing network, and
Table 5 lists the typical generated jitter performance.
Notes
1
2
Generated Jitter
Jitter Transfer
Characteristic
Characteristic
Repetitive “100 ” input at nominal DSX-3 level with V
Repetitive input data pattern at nominal DSX-3 level with V
= 5V T
T
All 1s pattern
Repetitive “100”
pattern
Peaking
Peaking
f 3dB
A
100
= 25°C.
40
Table 5. Generated Jitter and Jitter Transfer
80
60
20
0
Parameter
A
Figure 8. Phase Characteristic of 728A
1.0
= 25°C.
2
2
2.0
1
Coaxial Cable (450 ft.)
Characteristics
Frequency (MHz)
5.0
0.05
0.05
Typ
205
1.0
1.5
10
20
Max
ns peak-to-peak
ns peak-to-peak
50 100
Unit
kHz
dB
dB
DD
= 5V,
DD