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Design dilemma



Design dilemma | 13 August, 2001

Trying to find out if there are any data/articles/references out there that looks at the reliability of using SMC�s over interconnects(connectors).

The dilemma is having a daughter card with a board-to-board connector vs. having the components (discrete�s, uBGA�s, SOIC�s, etc.) mounted directly to the motherboard. Obviously there are trade-offs in cost, real estate, custom IC�s (?), etc., but I am trying to look at the improved reliability (if there are case studies showing such) in going with SMC�s. Any suggestions where I can find supporting ammo ???

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Design dilemma | 15 August, 2001

It would be nice if someone had the answer, but often situations like this are peculiar. What not build models of each and then wring them out?

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Design dilemma | 23 August, 2001

Hi delnosa,

Sorry about being 10 days late - don't get to the bottom of the page much. I'm working of layering flex circuits sandwiched between FR4 layers. The flex is primarily designed to take the place of interconnects like yours. I work in applications where the PCBs are in heavy-duty industry and sometimes SMT connectors fail. Basically, the two boards I'm mating are put together in one board layout, only being connected by the flex circuit and breakaway rails. No need to worry about connectors, opens up board real-estate, can be wave soldered like normal, and works great. Finding a board manufacturer might take a little searching and the cost is slightly higher, but you have to weigh your own costs. It also works great on multiple board designs - I have 4 different boards connected by flex, which all get sandwiched together into a housing.

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Michael Parker


Design dilemma | 23 August, 2001

That's slick - I like it - good to learn something new everday. Thanx

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