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Component Specifications

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John S.

#48035

Component Specifications | 28 February, 2007

We've been considering adding reflow, MSL, and other "process" specifications to our component drawings. Presently, we have a review process for component compatibility. Does anyone else try to enforce these specs? Has your experience been that the vendors will try to follow them, or just not tell you and risk a problem later on? It seems like a good idea for our purchasing folks, but I've always believed in buyer beware. Thanks John S.

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Rob

#48040

Component Specifications | 28 February, 2007

Hi John

My understanding of your post is that you are asking if anyone has tried to enforce MSL levels or reflow parameters onto the component vendor/manufacturer. Is this your question or am I mis-interpriting it?

If that is the case you will not get anywhere. It's up to a design engineer to specify in the right component for the right design & process. MSL levels and reflow profiles are by & large dictated by the package used, which are based on international (JEDEC) standards.

If you want to start calling the shots regarding parameters such as the above you start entering the realms of custom components, which puts the price through the roof as you lose the economies of sace from mass production.

Cheers,

Rob.

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#48046

Component Specifications | 28 February, 2007

Every component has a "how to order" paragraph in their data sheet with specific suffixes,letter/digit combinations that reflect each parameter of that part including packaging, lead finish etc. So if you order using the manufacturer p/n you are almost always going to receive what you need. In terms of MSL levels these are predetermined like Rob stated above and any special requests outside of the data sheet are very unlikely to be satisfied while still being cost effective. It takes a lot of engineering to develop a component with specific characteristics. Your component engineer should be able to specify exactly what you need way ahead of time.He/she should be knowledgeable about what is in production, obsolete or in development and help your buyers when questions arise. Most design team leaders evaluate components prior to design being released.

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John S.

#48049

Component Specifications | 28 February, 2007

Thanks guys. I'm always getting feedback from purchasing and design that we should just put this info on the spec sheet, but I've always argued that the vendors will either ignore it, or it will become a cost driver. Thanks John S.

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