VSC8115YA1 VITESSE [Vitesse Semiconductor Corporation], VSC8115YA1 Datasheet - Page 5

• Manufacturer Part Number: VSC8115YA1
• Description: STS-12/STS-3 Multi Rate Clock and Data Recovery Unit
• Manufacturer: VITESSE [Vitesse Semiconductor Corporation]

VSC8115
Target Specification
9/29/00
G52272-0, Rev. 1.1
Jitter Tolerance
data stream. The Bellcore and ITU specifications allow the received optical data to contain jitter. The amount
that must be tolerated is a function of the frequency of the jitter. At high frequencies the specifications do not
require the VSC8115 to tolerate large amounts, whereas at low frequencies many unit intervals (bit times) of jit-
ter have to be tolerated. Jitter tolerance is defined as the ratio of jitter on the output OC-N/STS-N signal to the
jitter applied on the input OC-N/STSN signal versus frequency. The VSC8115 is designed to tolerate this jitter
with margin over the specification limits, see Figure 2. The VSC8115 obtains and maintains lock based on the
data transition information. When there is no transition on the data stream, the recovered clock frequency will
be held to within +500ppm of the reference clock. The VSC8115 can maintain lock over 1000 bits of no switch-
ing on data stream.
Jitter Generation
to the serial data inputs. Maximum jitter generation is 0.01 U.I. when rms jitter of less than 14ps (OC-12) or
56ps (OC-3) is presented to the serial data inputs.
Jitter Tolerance is the ability of the Clock and Data Recovery Unit to track timing variation in the received
Jitter generation is defined as the jitter of the serial clock and serial data outputs while rms jitter is presented
0.15
150
1.5
15
J
ITTER
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: [phone]
Bellcore Requirement
(UI
10
P
Figure 2: Input Jitter Tolerance Specification
-
P
VITESSE
)
VITESSE SEMICONDUCTOR CORPORATION
SEMICONDUCTOR CORPORATION
30
300
25K
24
250K
2.4
1M
2.5M
0.6
VSC8115 Typical
Jitter Tolerance
Clock and Data Recovery Unit
J
ITTER
STS-12/STS-3 Multi Rate
F
REQ
(H
Z
)
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