Справочник Пользователя для Intel 820E

Design Guide 

 

185 

This design guide provides only examples. Many power distribution methods achieve similar results. 
When deviating from these examples in any way, it is critical to consider the effects of the change. 

In addition to the power planes provided by the ATX power supply, an instantly available Intel 820E 
chipset-based system (using Suspend to RAM) requires that seven power planes be generated on the 
board. The requirements for each power plane are documented in this section. In addition to on-board 
voltage regulators, the Intel 820E chipset reference board has a 5 V dual switch.  

This switch powers the 5 V dual plane from the 5 V core ATX supply during full-power operation. 
During Suspend to RAM, the 5 V dual plane will be powered from the 5 V standby power supply. Note: 
The voltage on the 5 V dual plane is not 5 V! The resistive drop through the 5 V dual switch must be 
considered. Therefore, no components should be connected directly to the 5 V dual plane. On the ICH2 
reference board, only the voltage regulators (for lower-voltage regulation) are connected to the 5 V dual 
plane.  

Note:  This switch is not required in an Intel 820E chipset-based system that does not support Suspend to RAM 

(STR). 

This power plane is used to power the Intel PGA370 socket processor.  

Refer to the latest revisions of the following documents: 

• 

• 

For the Intel 820E chipset/FC-PGA Vcc_vid requirements, refer to the Intel

 III Processor for the PGA370 Socket. These guidelines can 

be downloaded from the Intel website at: 

Note:  This regulator is required in all designs. 

This power plane is used to power the AGTL+ dual-ended termination and the 1.5 V power delivery to 
the Intel PGA370 socket processor. 

Refer to the latest revision of the following document: 

• 

For the Intel 820E chipset/FC-PGA VTT requirements, refer to the Intel

 III Processor for the PGA370 Socket. These guidelines can be 

downloaded from the Intel website at: 

Note:  This regulator is required in all designs. 

The Pentium III processor for the Intel PGA370 socket does not use this signal.