Control Signal To Clock Trace Length Matching Diagram - Intel 855GME Design Manual

®
Intel 855GME Chipset and Intel
Length range formula for DIMM1:
X = SCK[5:3]/SCK[5:3]# total reference length, including package length. Refer to
1
Section 5.4.3.1
Y = SCS[3:2]# and SCKE[3:2] total length = GMCH package length + L1, as shown in
1
where:
– 1.5") ≤ Y
(X
1
No length matching is required from the DIMM to the termination resistor.
length matching requirements between the control signals and clock. A nominal CS/CKE package
length of 500 mils may be used to estimate baseline Mbyte lengths.
Figure 70. Control Signal to Clock Trace Length Matching Diagram
GMCH Package
855GME
Note: All lengths are measured from GMCH
die pad to DIMM connector pads.
GMCH Package
855GME
Note: All lengths are measured from GMCH
die pad to DIMM connector pads.
System Memory Design Guidelines (DDR-SDRAM)
for more information.
≤ (X
- 0.5")
1 1
SCS#[1:0]
SCKE[1:0]
Die
SCK[2:0]
SCK#[2:0]
SCS#[3:2]
SCKE[3:2]
Die
SCK[5:3]
SCK#[5:3]
January 2007
®
6300ESB ICH Embedded Platform Design Guide
DIMM0
CTRL Length = Y0
(X0 – 1.5" ) ≤ Y0 ≤ (X0 - 0.5")
Clock Ref. Length = X0
DIMM0 DIMM1
Figure
Figure 70 depicts the
CTRL Length = Y1
(X1 – 1.5") ≤ Y1 ≤ (X1- 0.5")
Clock Ref. Length = X1
69,
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