I certainly do respect what you say, but doesn't this go back to electronic
assembly beginnings? I mean, we've always faced compromises from design
through customer acceptance.

I guess it's getting harder now, or is it just getting less DFM/CE
conscious. Engineers always cook up new needs based on market/customer
demand or what is perceived the market needs. They don't always see all the
way through all the processes required when effecting a design maybe based
on a single component. They certainly do not always consult with those who
know these effects and what is required to produce high quality assemblies
on time at the lowest cost and highest quality.

I keep going back, in my mind, to the early SMT days in the early '80's when
50 mil pitch stuff was the norm. At that time, I knew of many GOOD board fab
houses saying it would never be possible to get to 25 mils. Look at us now
and beyond. I also remember the days when RF engineers and designers
insisted on placing through holes in SMT pads and wondering why
solderability and chip component cracking were serious issues. Here too we
have come a long way in a short period.

Where I'm going with this is, as you know, there must be something amiss
when we have to profile a board around one or two components. Dorothy, as
you replied to another, remove the caps and replace them as you need. In
many cases, second ops are needed to handle unique devices. You know the
processes required as well - selective wave, etc.

As these compromises exist in every design we attempt. We must work together
more closely so one component doesn't hold up the show - either with better
device selections or better manufacturing capabilities. Having said that, it
is just too tough to profile a board focusing on such a wide temperature
range - between a few devices and so many others. It's better to effect a
better design or facilitate ways to add unique devices in a separate operation.

Earl Moon

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