S3033 AMCC (Applied Micro Circuits Corp), S3033 Datasheet - Page 21

• Manufacturer Part Number: S3033
• Description: Bicmos Lvpecl Clock Generator Sonet/sdh/atm Oc-12 Transmitter And Sonet/sdh/atm Oc-3/oc-12 Transceiver
• Manufacturer: AMCC (Applied Micro Circuits Corp)

S3035 WITH DATA CLOCK SYNCHRONOUS
TO REFERENCE CLOCK
In some applications it is necessary to "forward
clock" the data in a SONET/SDH system. In this ap-
plication the reference clock from which the High
speed serial clock is synthesized and the parallel
data clock both originate from the same (usually
TTL/CMOS) clock source. This application note ex-
plains how the AMCC S3035 can be configured to
operate in this mode.
Clock Control Logic Description
The timing control logic in the S3035 automatically
generates an internal load signal which has a fixed
relationship to the reference clock. The logic takes in
to account the variation of the reference clock to the
internal load signal over temperature and voltage.
Figure 13. S3035 with Data Clocked by Reference Clock
April 12, 2000 / Revision D
APPLICATION NOTE
SONET/SDH/ATM OC-3/12 TRANSCEIVER W/CDR
ASIC
Reference
Output
Output
Clock
Data
8
Data
The connections required to implement the design
are shown in Figure 13. The setup and hold times for
the PICLK to the data must be met by the controller
ASIC. It is recommended that the data on the falling
edge of the output reference clock be latched in or-
der to meet the required specifications.
Possible Problems
In order to meet the jitter generation specifications
required by SONET, the jitter of the reference clock
must be minimized. It may be difficult to meet the
SONET jitter generation specifications using a refer-
ence clock input with a TTL reference source.
PICLK
PIN[7:0]
S3035
REFCLK
Serial Data
S3035
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