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I wanted to become more familiar with BGA package PCB design and have selected a chip to learn with. This is a Texas Instruments DSP here. I've studied several 'BGA at home' guides and believe to have an understanding of what is required for design and assembly.

However, it seems like this chip requires very small traces compared to chips used in several guides I've read. This BGA package has a pitch 0.8mm and 0.55mm ball diamater. The resulting width between balls is ~10 mils. This seems like a pretty unfortunate pitch to ball diameter ratio.

I haven't even gotten to the assembly portion yet and this seems like it will be difficult to get a PCB printed that satisfies this spec.

My question: What is the recommended PCB trace width for navigating this 10mil gap?

How would a manufacturer do this? It seems like anything smaller than the typically 5 mil trace width would add further costs.

BGA footprint provided below:

enter image description here

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4 mil trace width is what we use on AM3354 processor. We have same pitch (.8mm) and ball size (.5mm). Don't know how we determined 4 mil works but we've been using it the past couple of years and run almost 50k boards.

FBGA packaging guidelines

enter image description here

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    \$\begingroup\$ Just for information. What is the maximum current for a 4 mil trace in the middle layers? \$\endgroup\$ – skvery Feb 15 '17 at 19:44
  • \$\begingroup\$ About 130 mA at .5 oz copper. \$\endgroup\$ – Samee87 Feb 15 '17 at 20:24

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