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Baking requirement

Yngwie

#19453

Baking requirement | 10 April, 2002

Temp/Humidity requirement for baking normally specified at :

Low Temp baking : 40 deg C at 5% RH High temp Baking: 125 Deg C at 5% RH.

The problem here is the 5% ? Although the 5% is achievable with a special Oven, can someone explain why is it 5% not 12% or 15% etc. ? in other words, what is the disadvantage of baking the moiture sensitive at 12% ? I'm quoting the 12% is b'cos, if I purge the N2 into our baking oven, I only manage to achieve 12%. production says, no point baking if the 5% is not met, despite knowing that baking at 12% is better than no baking.

2ndly,I was also told that the MQuad packages does not need the dry packaging as it is not sensitive to moisture, why is it ? what is the diff. with the normal QFP ?

Feedback is very much appreciated.

thanks.

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#19458

Baking requirement | 10 April, 2002

BAKING MSD AT 5% You can bake at any RH% you�d like. The further you get from 5%, the longer it takes. Those guys in production are just bustin� ya. For background, look at: * http://www.seikausa.com/mcdrysmt.pdf * http://www.aecouncil.com/Papers/aec8.pdf

BAKING MQUAD We don�t use that package [so we�re winging it a bit], but we know you only need to bake plastic packages. MQUAD [ http://www.advancedinterconnect.com/MQUAD.htm ] is not a plastic package [we think]. The �M� is for �metal�. They epoxy two pieces of anodized aluminum together to form the 'quad flat pack'.

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Yngwie

#19470

Baking requirement | 11 April, 2002

Thanx Dave..the doc are really informative.

cheers...and have a nice weekend.

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#19475

Baking requirement | 11 April, 2002

We have just introduced a new drying process that operates at only 55 deg. C and has proven to be able to drive moisture from tape and reeled devices or compontents in shipping tubes as effectively or more effectively as a convection oven at 125 deg C with the units in trays.

Contact me if you want more information.

Best Regards

Stu Leech

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Yngwie

#19539

Baking requirement | 17 April, 2002

Hi Stu Leech,

I've been trying to contact you thru' your e-mail address but failed to get any response. I'm very interested to know details on the new drying process i.e. operates at only 55 deg, that you were talking about.

Anyone with experience pls respond.

cheers...

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#19541

Baking requirement | 17 April, 2002

Stu Leech Altos Engineering sleechatixdotnetcom. Alternately, search the fine SMTnet Archives by company for Altos Engineering to obtain contact infomation. [Be careful. Glendale is not in 'Engineering'. It's in 'AZ'.]

Ask Stu about Croc-Clamps

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Yngwie

#19605

Baking requirement | 20 April, 2002

Thanx Dave.

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