Symbols on Drills layer 44

Question

Hi,

I am trying to place some very small feed-throughs between the pads on a BGA100 0.8 mm device.

I don't understand the white symbols shown on layer 44 on a board file for a feed through .

Using the Info button on a via, I can set the diameter to 0.485 and the drill to 0.25, which seems to fit well within the BGA pins.

The via is surrounded a white circle crossed by a white line at 45 degrees, both on layer 44.

What do the circle and line represent and where are their dimensions derived?

I assume that they are keep-out symbols but how can I change their values?

Thanks in advance for any help,

John.

ingit · Answer

"The via is surrounded a white circle crossed by a white line at 45 degrees, both on layer 44."\

Those layers are drill and hole layer they simply show that here is a hole that needed to be drilled out.

That lines will not affect anything. if it overlaps your BGA pin than also it will not affect. just a symbol not more than that.