Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Flex circuit

Views: 4486

#36792

Flex circuit | 22 September, 2005

Hi, I am having a problem with component position on a flex circuit. It is an eight up panel. The flex circuit is mounted on to a piece of fr4 with presure sensitive adhiesive, this is done out of house. The problem is, I will locate the parts on one board, and when I go to the next board the parts are slightly off position. They may be slightly different for all eight boards. Is this a problem with flex circuits, and what can be done to fix it?

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dougs

#36793

Flex circuit | 23 September, 2005

Sounds like your using global fids, if there are marks on each board use local fids and that should help.

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Rob

#36800

Flex circuit | 23 September, 2005

Yes it is a problem with nearly all flex's, & Doug's way is also the way we do it.

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#36807

Flex circuit | 23 September, 2005

I agree with the local fids concept. This is usually a problem since the flex will most likely not have fids. However if your components are 50-mil pitch and 1206 or larger, you could use tooling holes to align the flex circuits when they are attached to the carrier.

Jerry

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#36815

Flex circuit | 23 September, 2005

I have been using local fids, and the machine comes up with board stretch or shrink errors on some boards.

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PWH

#36816

Flex circuit | 23 September, 2005

Increase search box size for fids if you can.

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Ken

#36822

Flex circuit | 24 September, 2005

If your having placement problems are you having printing alignment problems?

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