![Xilinx VC709 Скачать руководство пользователя страница 29](http://html2.mh-extra.com/html/xilinx/vc709/vc709_user-manual_3386491029.webp)
VC709 Evaluation Board
29
UG887 (v1.2.1) March 11, 2014
Feature Descriptions
shows this AC-coupled clock circuit.
•
External user-provided GTH reference clock on SMA input connectors
•
1.8V differential input
Jitter-Attenuated Clock
[
, callout
]
The VC709 board includes a Silicon Labs Si5324 jitter attenuator U24 on the back side of the
board. FPGA user logic can implement a clock recovery circuit and then output this clock
to a differential I/O pair on I/O bank 13 (REC_CLOCK_C_P, FPGA U1 pin AW32 and
REC_CLOCK_C_N, FPGA U1 pin AW33) for jitter attenuation. The jitter-attenuated clock
(Si5324_OUT_C_P, Si5324_OUT_C_N) is then routed as a reference clock to GTH Quad 113
inputs MGTREFCLK0P (FPGA U1 pin AH8) and MGTREFCLK0N (FPGA U1 pin AH7).
The primary purpose of this clock is to support CPRI/OBSAI applications that perform
clock recovery from a user-supplied SFP/SFP+ module and use the jitter-attenuated
recovered clock to drive the reference clock inputs of a GTH transceiver. The
jitter-attenuated clock circuit is shown in
X-Ref Target - Figure 1-10
Figure 1-10:
GTH SMA Clock Source
S
MA_MGT_REFCLK_C_P
J26
GND
J25
GND
UG
88
7_c1_10_090612
S
MA
Connector
S
MA
Connector
S
MA_MGT_REFCLK_C_N
S
MA_MGT_REFCLK_N
S
MA_MGT_REFCLK_P
C25
C24
0.01
μ
F 25V
X7R
0.01
μ
F 25V
X7R
Содержание VC709
Страница 1: ...VC709 Evaluation Board for the Virtex 7 FPGA User Guide UG887 v1 2 1 March 11 2014...
Страница 66: ...66 www xilinx com VC709 Evaluation Board UG887 v1 2 1 March 11 2014 Chapter 1 VC709 Evaluation Board Features...
Страница 70: ...70 www xilinx com VC709 Evaluation Board UG887 v1 2 1 March 11 2014 Appendix B VITA 57 1 FMC Connector Pinouts...
Страница 92: ...92 www xilinx com VC709 Evaluation Board UG887 v1 2 1 March 11 2014 Appendix C Master XDC Listing...
Страница 96: ...96 www xilinx com VC709 Evaluation Board UG887 v1 2 1 March 11 2014 Appendix E Board Specifications...