I/O Controller Hub 2
R
Intel
®
Pentium
®
4 Processor / Intel
®
850 Chipset Family Platform Design Guide 179
9.9.4.6.1 Termination Plane Capacitance
It is recommended that the termination plane capacitance equal a minimum value of 1500 pF. This
helps reduce the amount of crosstalk on the differential pairs (TDP/TDN and RDP/RDN) from the
unused pairs of the RJ45. Pads may be placed for an additional capacitance to chassis ground,
which may be required if the termplane capacitance is not large enough to pass EFT (Electrical
Fast Transient) testing. If a discrete capacitor is used, to meet the EFT requirements it should be
rated for at least 1000 Vac.
Figure 127. Termination Plane
N/C
RJ-45
Magnetics module
RDP
RDN
TDP
TDN
Termination plane
Additional capacitance that may be
required for EFT testing
LAN_term_plane