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I know that for signal integrity, the PCB traces are always considered to be part of the electrical circuit.

How should traces be considered in different situations, like high current, RF, high edge rates etc.?

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  • \$\begingroup\$ Why don't you narrow your question down a bit. Maybe "What factors influence PCB trace design for power deliver?". \$\endgroup\$
    – SteveSh
    Nov 21, 2020 at 14:47
  • \$\begingroup\$ Precision is another area where the non-zero impedance of PCB traces need to be considered. \$\endgroup\$ Nov 21, 2020 at 17:10

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I know that for signal integrity, the PCB traces are always considered to be part of the electrical circuit.

Not always. Slow edge digital signals, non-precision low current analogue circuits, will usually get away with anything.

How should traces be considered in different situations, like high current, RF, high edge rates etc.?

For high current, the resistance of the track is usually significant. Make sure it's wide enough.

For RF and high edge rates, the length is significant if it is longer than fraction of the wavelength of the signal or edge. Then some form of controlled impedance for the line, and matching to it, is needed at one or both ends of the track, depending on how the line is being used.

In precision analogue, you need to make sure a current through the resistance or inductance of a trace doesn't generate a voltage that's impressed on some other part of the circuit that it should not be. This is often easier said than done.

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  • \$\begingroup\$ Ok, got it! Thank you! Maybe some other cases exists, where PCB traces should be treated differently? \$\endgroup\$
    – Andy
    Nov 21, 2020 at 15:57
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In precision voltage reference applications (analog), capacitance is the primary consideration, usually precluding a ground plane. In fact, up until the 1990s, zener-based references were hand-made.

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