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Roibert , 12-25-2021, 06:16 AM

Dear Forum

Starting from a Schematic , exist some theorical calculation that can suggest me what could be the minimul layer to use in base to some criteria? (for example in base to component number or net number ecc)
Have Altium some help for this decision?

Thanks in advance
Roberto

qdrives , 12-30-2021, 10:07 AM

It is not the number of components, nor the number of nets.
It is mainly the component density (pin density), clearance requirements (i.e. voltage and crosstalk), speed and power (Gnd and power layers) and security requirements.
Then there is the copper thickness (minimum width and spacing), cooling through the PCB (lowers density), current carrying requirements, mounting, VIA types, number of vias and through holes.
Happy Holden was able to calculate this for high speed designs, but they were using something like 18 layers (and 10 using HDI).

Roibert , 12-31-2021, 02:35 AM

Thanks for reply

So, how do you proced when designing a new PCB ? For example, you start with N layer (N signal layer...apart POWER and GND plane ) ,and then increase the N when you have impossibility to continue ? And What N you decide at begnin...just with exerience?

Have Altium some exstimator ?

Thaks again for your reply

Roberto

robertferanec , 01-03-2022, 01:55 AM

Some time ago I created a post on this topic. Maybe it can help:
3 STEPS How to determine / calculate number of PCB layers https://welldoneblog.fedevel.com/201...of-pcb-layers/

Roibert , 01-03-2022, 02:20 AM

Thanks very much for your reply.

Roberto

qdrives , 01-03-2022, 08:51 AM

@Roibert I have only designed up to 6 layers. For one of the designs I started with 4, but in the end I had to increase to 6. This made the design not as good as it could be, but there was no more time for improvement. For all other designs I did, I never had to change the layer count during layout.

Ashish1710 , 01-05-2022, 11:44 PM

@robertferanec And @qdrives How to calculate Component density (Pin density ) of PCB.
On which Parameter mostly we decide for PCB design

robertferanec , 01-10-2022, 01:10 AM

It's a lot about fanout. You need enough layers to be able to take out all the pins from the biggest and most complex BGA component on your board. Everything else is mostly about size of the board - smaller the board is, more layers you may need. There is no simple calculator - when you do layout planning you will be able to find out how many layers you will need: https://youtu.be/kXBX4gFQB4o