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Eoliveira , 07-20-2018, 05:39 PM

Hello Robert !!!
Hello Everyone !!!

I'm starting a new board.using MCU. My questions are:

1. What's the VIA specification to this type of Board ?

2. How to setup correct stack up ?

3. Could I use the same idea /way than 2 layers PCB ?

Thank you very much

robertferanec , 07-24-2018, 03:04 AM

Hello @Eoliveira
​1. Depends how complex and expensive / cheap the board needs to be. For cheaper boards I use VIA diameter 0.6mm and hole size 0.3mm. For more complex boards I use 0.45mm / 0.2mm
2. This may help you: https://www.fedevel.com/welldoneblog...of-pcb-layers/
3. I am not sure what you mean.

Eoliveira , 07-24-2018, 02:27 PM

@robertferanec

About question number 3.

- Try to keep GND on the bottom as solid as possible, route as much as possible on the top.

- Is necessary to use polygon on bottom or Top Layer for GND ?

- Route short tracks on the bottom, ( horizontal routing ), and keep the GND as big as possible on the bottom layer.

This new board is simple, but I would like to have 4 layers.
.
My last board I used 2 layers, In my point of view is very hard supply some parts of circuit.

Thank you

robertferanec , 07-25-2018, 11:31 AM

For 4 layer PCB ideally you would like to use one inner layer as a solid GND plane with no other tracks. The other inner layer can be used for power planes. Than I would use TOP and BOTTOM layers for routing rest of the signals.

Eoliveira , 07-26-2018, 07:58 AM

@robertferanec
Thank you very much !!!

chitransh92 , 07-26-2018, 10:52 AM

Hello,
I am trying to get the current carrying capacity of a via using "Saturn PCB Toolkit" and my questions are :-

1.What is "Ideal Plane clearance" for the Vias which can be used and what is its selection based on?
2.If I am using a via on a track, how should I find out the "Reference plane opening" to input in the Saturn PCB toolkit.

Thanks!

robertferanec , 07-26-2018, 11:51 PM

@chitransh92 I don't think that influences VIA current capacity. Did you try to change it and check the VIA current?

chitransh92 , 07-27-2018, 12:00 AM

You are right Robert, it does not affect the current carrying capacity.
However, I am also interested to know the significance of "Plane clearance" and how do we select it in our designs.

robertferanec , 07-27-2018, 12:18 AM

Often I use minimum clearance. Usually, during PCB manufacturing, the unconnected pads are removed from the inner layers anyway.

chitransh92 , 07-27-2018, 12:20 AM

Robert,
Need some more clarity here.

Minimum clearance = 0.1 mm or some other value.