Intel 6300ESB ICH, Design Manual

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Intel
®
855GME Chipset and Intel
®
6300ESB ICH Embedded Platform Design Guide
be placed within 0.5 inches of their respective pins and connected with a 15 mil wide trace. To
avoid coupling with any other signals, maintain a minimum of 25 mils of separation to other
signals.
4.8.3.4 GMCH Analog Power
Table 25 summarizes the eight analog circuits that require filtered supplies on the GMCH. They
are: VCCASM, VCCQSM, VCCAHPLL, VCCADPLLA, VCCADPLLB, VCCADAC,
VCCAGPLL, and VCCALVDS. VCCADAC, VCCAGPLL, and VCCALVDS do not require an
RLC filter but do require decoupling capacitors.
Figure 62 depicts an example analog supply filter.
Figure 61. GMCH HXSWING and HYSWING Reference Voltage Generation Circuit
R1a
301
R2a
150
C1a
+VCCP
Intel®
855GME
Chipset
GMCH
HXSWING
HXSWING HYSWING
R1b
301
R2b
150
C1b
+VCCP
HYSWING
Figure 62. Example Analog Supply Filter
Low Pass Filtering
Noise
L
C
BULK
C
HIGH
V
CC
Filtered V
CC
†
R
DAMP
†
R
DAMP
†
R
DAMP
is not required for all
filters