Intel 820E Benutzerhandbuch

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Intel
®
 820E Chipset 
 
 
 
 
R
 
40  
Design 
Guide 
Figure 19. Incorrect Direct RDRAM* Ground Plane Referencing 
3.3-V Plane
1.8-V Plane
MCH
Wrong
dir_Rambus_gnd_plane_ref_incorrect
RIMM2
RIMM1
 
Figure 20. Direct RDRAM* Ground Plane Reference 
Extend GND plane
reference island beyond
V
TERM
 capacitors
GND Plane
1.8-V Plane
RIMM1
GND Plane
GND Plane
MCH
Required
Vterm layer not shown
V
TERM
 resistors
V
TERM
 capacitors
dir_Rambus_gnd_plane_ref
RIMM2
3.3-V Plane
 
The ground reference island under the RSL signals MUST be connected to the ground pins on the RIMM 
connector and the ground vias used to connect the ground isolation on the first and fourth layers.