On 01:12 PM 1/06/2002 -0500, David W. Gulley said:
Richard Sumner wrote:
David,
Talk to your assembler before you invest time in this. The paste mask
becomes a metal stencil for applying the solder paste. So donuts will not
work (the donut hole is unsupported).
Actually my idea was to make
Ian,
For some reason when I originally went to put a pad on the top solder
layer, I could not find it! I am not sure what I had done, but my best
guess is that I was trying to place a via rather than a pad.
Thanks for getting me to recheck this, as I do not like to use the
update
On 10:47 AM 3/06/2002 -0500, David W. Gulley said:
Ian,
For some reason when I originally went to put a pad on the top solder layer
(I think you mean Top Solder Mask layer here - for any other reader coming
along later that might get confused.)
, I could not find it! I am not sure what I
At 10:57 AM 6/1/2002 -0500, David W. Gulley wrote:
I am doing some via-in-pad BGAs and need to figure out if there is a
good way to provide the top solder and top paste masks while keeping the
bottom solder mask and bottom paste masks off.
I defined the BGA pads as multilayer since I am doing
My mistake...sounds like you Steve found the same solution (SMT pad +
via), sounds good to me.
-Original Message-
From: David W. Gulley
Sent: Saturday, June 01, 2002 2:59 PM
I do not want a circular block in the center of the pad.
snip
How would you place a circle on the paste
I am doing some via-in-pad BGAs and need to figure out if there is a
good way to provide the top solder and top paste masks while keeping
the bottom solder mask and bottom paste masks off.
I defined the BGA pads as multilayer since I am doing via-in-pad (sort
of like it was a PGA) except I do
are you sure you don't want the bottom pads untented?
a recent customer specifically wanted the bottom via fanouts to be
untented for test probing
(i realize yours are in pad)
your via in pad only goes to the layer below, right?
in my understanding this is the only way it can be small enough to
Richard Sumner wrote:
David,
Talk to your assembler before you invest time in this. The paste mask
becomes a metal stencil for applying the solder paste. So donuts will
not work (the donut hole is unsupported).
Actually my idea was to make the width of the track greater than 2x the
boy that's some tight stuff, good luck! and keep us posted
Dennis Saputelli
David W. Gulley wrote:
Dennis Saputelli wrote:
are you sure you don't want the bottom pads untented?
a recent customer specifically wanted the bottom via fanouts to be
untented for test probing
(i
If I understand this, it still can't work. The paste-mask stencil has an
opening for the pad, and you want a circular block in the center of the
pad -- but there's nothing to support it.
-Original Message-
From: David W. Gulley
Sent: Saturday, June 01, 2002 11:13 AM
Richard Sumner
I do not want a circular block in the center of the pad.
For this board using Via in Pad:
The board fabrication process drills a through hole through the board
and plates the holes (so far just like any other plated hole). Then they
plug the hole in the BGA pads using a process that leaves the
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