Xilinx Virtex-6 FPGA User Manual page 189

Table 4-6
shows the Use Mode 3 configuration.
Table 4-6: RX Termination Use Mode 3 Configuration and Notes
External
Use Mode AC
Voltage
Coupling
3 ON
X-Ref Target - Figure 4-5
Board
~100 nF
~100 nF
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Virtex-6 FPGA GTX Transceivers User Guide
UG366 (v2.5) January 17, 2011
outlines the recommended settings for RX termination in Use Mode 3.
Term Internal AC Internal
Coupling Bias
Float OFF 800 mV
FPGA
MGTAVTT_*
ESD Diodes
nominal
50Ω
nominal
50Ω
MGTAVTT_*
ESD Diodes
Figure 4-5: RX Termination Use Mode 3 Configuration
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Max
Swing Suggested Protocols and Usage Notes
mV
DPP
1600 Protocol: Optical IF (SONET/SDH/OTU),
SFP+, HD/SD-SDI, XAUI (1600 mVdpp), GbE,
DisplayPort (1.2V option)
Attribute Settings:
AC_CAP_DIS = TRUE
RCV_TERM_GND = FALSE
RCV_TERM_VTTRX = FALSE
Notes:
Similar to Case 2, but for interfaces with
> 1200 mV swing. This option has a lower
bandwidth than Case 2.
nominal 7 pF
nominal
50 KΩ
nominal
50 KΩ
nominal 7 pF
RX Analog Front End
Figure 4-5
V
CM
2/3 MGTAVTT_*
UG366_c4_05_071009
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