PCB panellization -- request information

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Could some electronics guru please
shed some light on the following ?
Recently, a colleague of mine was
discussing the PCB panellization
technique, where a large PCB board
can consist of a number of smaller
boards, and after fabrication, this
large board is cut up into a number
of smaller boards, each for a slightly
different use.
What puzzled us was how in this case
would the Berber files be organized.
I have some familiarity with Gerber
files, and it was not clear how the
fabrication details for two(for
example) separate PCBs be included
in the same Gerber file, given that
they are PCBs for different purposes.
Is it the case that the initial layout
is done in way that at the time of
Gerber file generation, they come
out as layout details for two
separate PCBs, but included in the
same Gerber file ? Any hints, ideas
or relevant pointers to information
would be greatly appreciated. Thanks
in advance.

 

[John Devereux]

Could some electronics guru please
shed some light on the following ?
Recently, a colleague of mine was
discussing the PCB panellization
technique, where a large PCB board
can consist of a number of smaller
boards, and after fabrication, this
large board is cut up into a number
of smaller boards, each for a slightly
different use.
What puzzled us was how in this case
would the Berber files be organized.
I have some familiarity with Gerber
files, and it was not clear how the
fabrication details for two(for
example) separate PCBs be included
in the same Gerber file, given that
they are PCBs for different purposes.
Is it the case that the initial layout
is done in way that at the time of
Gerber file generation, they come
out as layout details for two
separate PCBs, but included in the
same Gerber file ? Any hints, ideas
or relevant pointers to information
would be greatly appreciated. Thanks
in advance.

Usually you can do it yourself - the pcb software has a "panelization"
tool or "step and repeat". The gerbers then show the full panelized
artwork (an array of individual circuits). You put the scoring lines on
the fab layer (or on another one).

Alternatively the PCB supplier can do it for you. But remember any
solder paste stencil has to match so this can complicate things if this
is done by someone else, since you won't have the matching gerbers then.

In the special case of multiple designs on the same panel, you can just
present this as a single gerber with an array of circuits again with
scoring lines shown as before. In principle this should make no
difference but most do charge extra in my experience. I guess it is
harder for them to QC / test.

 

[Martin Riddle]

Could some electronics guru please
shed some light on the following ?
Recently, a colleague of mine was
discussing the PCB panellization
technique, where a large PCB board
can consist of a number of smaller
boards, and after fabrication, this
large board is cut up into a number
of smaller boards, each for a slightly
different use.
What puzzled us was how in this case
would the Berber files be organized.
I have some familiarity with Gerber
files, and it was not clear how the
fabrication details for two(for
example) separate PCBs be included
in the same Gerber file, given that
they are PCBs for different purposes.
Is it the case that the initial layout
is done in way that at the time of
Gerber file generation, they come
out as layout details for two
separate PCBs, but included in the
same Gerber file ? Any hints, ideas
or relevant pointers to information
would be greatly appreciated. Thanks
in advance.

Board manufactures typically use 12"x12" or even 24"x24" formats to
build the PCB layer by layer. The gerbers or artwork is repeated
across the Panel to inprove yield and also for manufacturing/stuffing
pruposes.

THe scoring you refer to is called V-scoring and ther is a special
"pizza' cutter to cut the boards down to the final shape.

But usually the panel, once it is fabricated, is then stuffed. Either
with thru-hole or Pick and place SMT parts. Then wave soldered or run
thru an IR oven for SMT. For SMT there are Fiducal marks out side the
V-score area that help the pick and place machines line up the smt
parts. After stuffing the Edges and with the fiducial marks are cut
off at the v-score.
Half way down this page is a V-score example
<http://www.4pcb.com/pcb-cam-based-quoting/>

Cheers