Intel 820E Benutzerhandbuch

122  

Design 

Guide 

• 

Traces from magnetics to connector must be shared and not stubbed. An RJ-11 connector that fits 
into the RJ-45 slot is available. Any amount of stubbing will destroy both HomePNA* and Ethernet 
performance. 

The ICH2 can generate large current swings when switching between logic high and logic low. This 
condition could cause the component voltage rails to drop below the specified limits. To avoid such a 
situation, ensure that the appropriate amount of bulk capacitance is added in parallel with the voltage 
input pins. It is recommended that the developer use the number of decoupling capacitors specified in the 
following table, to ensure that the component maintains stable supply voltages. The capacitors should be 
placed as close as possible to the package. Refer to Figure 78 for a layout example. For prototype board 
designs, it is recommended that the designer include pads for extra power plane decoupling caps. 

3.3 V core 

6 

0.1 

3.3 V standby 

1 

0.1 

processor I/F (1.3 – 2.5 V) 

1 

0.1 

1.8 V core 

2 

0.1 

1.8 V standby 

1 

0.1 

5 V reference 

1 

0.1 

5 V reference standby 

1 

0.1