Intel 41210 EMI Considerations, General Routing Guidelines, PCB Ground Layout Around Connectors

Models: 41210

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General Routing Guidelines

General Routing Guidelines

Figure 11. Crosstalk Effects on Trace Distance and Height

H

 

 

 

 

P

 

 

Reduce Crosstalk:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- Maximize P

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

aggressor

 

victim

- Minimize H

 

 

 

 

 

 

 

Reference Plane

A9259-01

Avoid slots in the ground plane. Slots increases mutual inductance thus increasing crosstalk.

Make sure that ground plane surrounding connector pin fields are not completely cleared out. When this area is completely cleared out, around the connector pins, all the return current must flow together around the pin field increasing crosstalk. The preferred method of laying out a connector in the GND layer is shown in Figure 12.

Figure 12. PCB Ground Layout Around Connectors

Connector

Connector Pins Figure 11. Crosstalk Effects on Trace Distance and HeightFigure 12. PCB Ground Layout Around Connectors

GND PCB Layer

A. Incorrect method

B. Correct method

A9260-01

6.3EMI Considerations

It is highly recommended that good EMI design practices be followed when designing with the 41210 Bridge.

To minimize EMI on your PCB a useful technique is to not extend the power planes to the edge of the board.

Another technique is to surround the perimeter of your PCB layers with a GND trace. This helps to shield the PCB with grounds minimizing radiation.

The below link can provide some useful general EMI guidelines considerations:

http://developer.intel.com/design/auto/mcs96/applnots/272673.htm

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Intel® 41210 Serial to Parallel PCI Bridge Design Guide

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Intel 41210 manual EMI Considerations, General Routing Guidelines, Crosstalk Effects on Trace Distance and Height