Intel 386 manual Closed Loop Signal Paths are Undesirable

PHYSICAL DESIGN AND DEBUGGING

The design of effective decoupling and bypass schemes centers on maximizing the charge stored in the circuit bypass loops while minimizing the inductances in these loops. Some other precautions that can minimize the EMI are as follows:

•Running a ground line in between two adjacent signal lines. The extra line should be grounded at both ends.

•The address and data buses can also be separated by ground lines. This technique may be expensive due to large number of address and data lines.

•Removing closed-loop signal paths that can create inductive noise (as shown III Figure 11-23).

Minimizing cross-talk involves first examining the circuit's interconnection with its near- est neighbors since parallel and adjacent lines can interact and cause EM!. It is neces- sary to maximize the distance between adjacent parallel wires.

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Figure 11-23. Closed Loop Signal Paths are Undesirable

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