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PCB bga fanout options, laser vias price?

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pasau

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Hi, i am working on a design with this chip: https://www.digikey.com/product-detail/en/csr-plc/CSR8675C-IBBH-R/CSR8675C-IBBH-RDKR-ND/5423495

It is 0.5mm pitch, ball diameter of 0.3mm, and my landing pads are 0.25mm. After much research i came across 3 options to do the fanout on my PCB, and i would like to minimize the cost. The options are:

1- dog-bone
2- via-in-pad
3- traces between pads

i know each of them have there advantages and all, but i would like to get a rule-of-thumb approximative comparison of pricing depending what technology i require, and possibly other advantages.

1- needs small micro-vias technology (~0.075mm laser drill) + 0.075 to 0.1 track width and clearance for the annular ring. I cannot fit more than 10 mils for total via size in dog-bone way.
2- need mfg that support via-in-pad, but drill size can be much bigger than option 1. i can use 6mils drill, so probably cheaper
3- need 3/3 mils track width/clearance to pass between pads.

In all 3 options i will most likely use blind and buried vias.

Option 1 seems to be the most interesting option, but not all mfgs support laser drill, and i don't want to go for an option that is 10x more expensive than the others, so i need to get an idea of prices in general.

thanks in advance!
 

Firstly as BGA is hard metric use metric for ALL your dimensions.... makes life easier and more accurate...
You cannot dog bone a 0.5mm BGA use via in pad and two to three HDI layers... or more if required.
 
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    pasau

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You cannot dog bone a 0.5mm BGA use via in pad and two to three HDI layers... or more if required.

really? according to texas pcb guidelines, and others "At the 0.5mm pitch, there is sufficient space between pads to allow for a via that has the same dimension as the package ball pad. The pad and via are connected with a 200um wide trace."
https://www.ti.com.cn/cn/lit/an/sprabb3/sprabb3.pdf
 

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