Mch Reference Voltage - Intel 855PM Design Manual

Platform Design Checklist
14.6.6.

MCH Reference Voltage

Pin Name
AGPREF
HI_REF
HVREF[4:0]
302
MCH – Reference Voltage
System
Pull up/Pull down
Voltage divider 1 k ± 1%
(top & bottom)
Voltage divider 100
± 1%
(top & bottom)
See Notes
49.9
(top)
100
(bottom)
- 150 HIVREF(ICH4-M signal), HI_VSWING (ICH4-M signal),
and HI_REF(MCH signal) may share a common hub
interface reference voltage divider if the divider is
located within 3" from both the MCH and ICH4-M.
See Figure 157 and Section 8.4 for more details.
For each of the 3 signals, a locally generated hub
interface reference voltage divider must be used if the
common reference voltage divider is located more than
3" away from the component.
See Figure 158 and Section 8.4 for more details.
± 1% Place R1 close to HVREF4 (ballout AB16) and R2
close to HVREF1 (ballout P8).
See Figure 155.
± 1%
R1a = 49.9 ± 1%
R2a = 100 ± 1%
C1 = 200 pF C2 = 200 pF C3 = 1 µF
See Section 4.1.7 for routing requirements.
®
Intel 855PM Chipset Platform Design Guide
Notes
R