Design Guide
Platform Design Checklist
R
Intel
®
855GM/855GME Chipset Platform Design Guide 307
Figure 155. Single or Locally Generated GMCH and ICH4-M HIVREF/HI_VSWING Circuit
ICH4-M
HIREF
R3
R2
C3
C4
VCCHI=1.5V
C1
C2
HI_VSWING
R1
GMCH
PVSWING
HLVREF
C5
C6
Option 1
R1 = 226
Ω
±
1%,
R2 = 147 Ω ± 1%,
R3 = 113 Ω ± 1%
Option 2
R1 = 80.6
Ω
±
1%,
R2 = 51.1
Ω
±
1%,
R3 = 40.2
Ω
±
1%
Option 3
R1 = 255 Ω ± 1%,
R2 = 162 Ω ± 1%,
R3 = 127
Ω
±
1%
C1 and C3 = 0.1 µF
(near divider)
C2, C4, C5, C6 =
0.01µF (near
component)
Intel
®
ICH4
HIREF
R3
R2
C4
VCCHI=1.5V
C2
HI_VSWING
R1
GMCH
HLVREF
R3
R2
C4
VCCHI=1.5V
C2
PVSWING
R1
Figure 156. Single Generated GMCH and ICH4-M VSWING/VREF Reference Voltage/ Local Voltage
Divider Circuit for VSWING/VREF
HIREF
V
CC
HI=1.5V
Intel
®
ICH4
R4
R5
C1
HI_VSWING
C3
R6
R7
HLVREF
PVSWING
C5 C2
C4
C6
GMCH
R4 = 43.2
Ω
±
1%,
R5 = 49.9
Ω ± 1%,
R6 = 78.7
Ω ± 1%,
R7 = 24.2
Ω ± 1%
C1 and C3 = 0.1 µF
(near divider)
C2, C4, C5, C6 =
0.01µF (near
component)