Guide

System Memory Design Guidelines (DDR-SDRAM)
R
Intel
®
852GM Chipset Platform Design Guide 125
7.3.7.4. CPC Group Package Length Table
The package length data in the table below should be used to match the overall length of each CPC
signal to its associated clock reference length.
Table 47. CPC Group Package Lengths
Signal Pin Number Pkg Length (mils)
SMA[1] AD14 398
SMA[2] AD13 443
SMA[4] AD11 430
SMA[5] AC13 346
SMAB[1] AD16 427
SMAB[2] AC12 395
SMAB[4] AF11 716
SMAB[5] AD10 631
7.3.8. Feedback – RCVENOUT#, RCVENIN#
The Intel 852GM GMCH provides a feedback signal called “receive enable” (RCVEN#), which is used
to measure timing for the read data.
In the Intel 852GM GMCH implementation of the GMCH the RCVENOUT# signal is shunted directly
to RCVENIN# inside the package in order to reduce timing variance. With this change it is no longer
necessary to provide an external connection. However, it is recommended that both signals be
transitioned to the bottom side with vias located adjacent to the package ball in order to facilitate
probing.
7.4. System Memory Compensation
See Section 12.5.3.3 for details.
7.5. SMVREF Generation
See Section 12.5.3.2 for details.
7.6. DDR Power Delivery
See Section 12.5 for details.