Micro Via Setup/Limitations

Question

I'm trying to create a PCB with a BGA component and I'm struggling with getting micro vias to work. Currently my setup is [2:(1*(2*(3*14)*15)*16):15] but I can only get a micro via to go down one layer whereas I need it to get down to the third layer. What is the proper setup for micro vias in eagle and are there limitations in how deep a micro via can go?

Best Regards

autodeskguest · Answer

"Osi Van Dessel" skrev i nyhetsmeldingen:

384052329.461415728160817.JavaMail.jive@flmspu-csapp-02.premierfarnell.com

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I'm trying to create a PCB with a BGA component and I'm struggling with
getting micro vias to work. Currently my setup is
[2:(1(2(314)15)*16):15] but I can only get a micro via to go down
one layer whereas I need it to get down to the third layer. What is the
proper setup for micro vias in eagle and are there limitations in how
deep a micro via can go?

This is a limitation of the manufacturer only. If you really want to do this

and are aware of the high costs, I suggest you google for standard HDI

types.

As an extract, you have the choise of different microvias in the "HDI type

2" standard:

- stacking mirovias on top of each other

- use staggered type (microvia between layer 2-3 slightly offset from 1-2)

- stepped microvia (1-2 slightly larger diameter than 2-3).

- skipped microvia (direct from 1-3 with no connect to 2). (I dont think

Eagle can DRC this)

Make sure you agree what the manufacturer can do, and the cost is within

your reach before you start designing.

Maybe this is the stackup you look for: