Vcc-Mch Output Requirements; Thermal Power Dissipation; Figure 49. Vccp Block Diagram; Figure 50. Vcc-Mch Block Diagram - Intel 855PM Design Manual

Platform Power Requirements
resistor network. See Figure 49. V
selection of R5 & R6 in the resistor network.
Figure 49. V Block Diagram
CCP
5.5. V
CC-MCH
The V
CC-MCH
V is 1.2 V. The voltage regulator can be programmed via an external resistor network. See Figure
CC-MCH
50. V is used to set the highest output voltage in conjunction with the selection of R7 and R8 in the
REF
resistor network..
Figure 50. V Block Diagram
CC-MCH
5.6.

Thermal Power Dissipation

Power dissipation has traditionally been a thermal/mechanical challenge for mobile system designers.
The amount of current required from the processor power delivery circuit and the heat generated by
processors has increased as processor frequencies go up and the silicon process geometry shrinks. The
package of any integrated device can only dissipate so much heat into the surrounding environment. The
98
is used to set the highest output voltage in conjunction with the
REF
Voltage
Regulator
V
REF
Output Requirements
output rail provides power to the core of the Intel 855PM MCH. The nominal voltage of
Voltage
Regulator
V
REF
V
CCP
* +/-0.1%
Tolerance
Recommended
R6 *
R5 *
V CC_MCH
* +/-0.1%
R7 * Tolerance
R8 *
Recommended
®
Intel 855PM Chipset Platform Design Guide
Intel Pentium
M processor
Intel 855PM
MCH
Intel 82801DBM
ICH4M
ITPFLEX
Intel
855PM
MCH
R