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What is the best stack-up design and layer order for 4-layer PCB? Signal/Ground/Core/Power/Signal is a good stack-up design? Or Ground/Signal-Power/Core/Signal-Power/Ground is better? Which is the best way?

And what should I think about the stack-up design? Which parameters are important for me? EMI/EMC issues important but is there any parameter important for 4-layer stack-up design?

jacks
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    define 'better' – Neil_UK Nov 28 '22 at 21:19
  • @CShark ... that other question is about 7.4 kV circuits, pretty unlikely this question is about such high voltage boards. – jonathanjo Nov 28 '22 at 23:08
  • By far the best thing you can do to address EMI/EMC issues is to learn the technical reasons why they exist and NOT seek a simple "paint by numbers" or "Just do this" solution. Understanding is 1000x more useful. A read though a relatively basic book such as "High Speed Digital Design: A Handbook of Black Magic" will be amazingly useful to you now and in the future. – Kyle B Nov 29 '22 at 02:36
  • "Which parameters are important for me?" That's a question you should ask yourself before asking for opinions. "What is best" is a pointless question without specifying "best". 4 ground layers is surely the "best" because there will be no voltages so nothing can break and it also has the best shielding and cooling by far compared to any other stack up. So go with 4 ground layers, obviously. – Lundin Nov 29 '22 at 15:17

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Signal - GND - GND - Signal is a typical choice. It allows you to have continuous ground planes to minimize ground loops and have solid impedance matching of signals. Typically for impedance control the outer layers are 0.15-0.4 mm thich.

You may have some power planes on any layer too, as long as the ground planes are continuous for return currents. Typically there's room for a powerplane in 6+ layer boards.

Ralph
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It is possible to reference a signal to a power plane, but usually it’s not wise to do. Problems start when signals travel trough via’s and a reference discontinuity happens. (Preventable with two GND planes and a GND via next to the signal via) Connecting power and ground by caps is not effective enough, because of the big loop.

The capacitance between power and ground plane is very small. And power usually is easily routed. (20 mils trace usually is ok)

RemyHx
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