请教过孔与焊盘问题

BGA封装的,间距太小,0.75mm

多层板

在顶层不打孔,打算用埋孔,用一个中间信号层与顶层的焊盘联系,然后由底层布线,,,但是不清楚中间的信号层与顶层的焊盘怎么连接?

  埋孔怎么弄?

急盼...

don’t understand your question！ it is impossible to connect signals from one layer to another with out via holes.

you can use “blind via holes” from top or bottom to middle layers, “buried via holes” are used for conections between middle layers