Intel 31154 manual Power Considerations, Analog Power Pins

P_VCCA Filter

S_VCCA Filter

	Power Considerations
Power Considerations	8

8.1Analog Power Pins

The analog voltage pins S_VCCA and P_VCCA require a low-pass filter. This is implemented by connecting the P_VCCA and S_VCCA pins to a 10 Ω series resistor and 0.01 ∝F and 4.7 ∝F (low- ESR) capacitors in parallel going to ground. The opposite end of the 10 Ω resistor is connected to the 1.3 V supply. This arrangement is shown in Figure 18 and Figure 19.

When implementing these circuits, use the following filter circuit layout and component recommendations:

1. Low-ESR, polymerized organic capacitors are recommended for 4.7 ∝F.

2. The 0.01 ∝F capacitor must be a X5R, X7R, or COG.

3. The capacitors must be placed as close as possible to associated pins to minimize inductance.

4. The connections from the P_VCCA and S_VCCA must be kept as short as possible.

Figure 18.

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Figure 19.

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Intel® 31154 133 MHz PCI Bridge Design Guide Design Guide 57