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Subject:
From:
Yuan-chia Joyce Koo <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Yuan-chia Joyce Koo <[log in to unmask]>
Date:
Thu, 9 Nov 2017 19:41:01 -0500
Content-Type:
text/plain
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text/plain (296 lines)
i am not question the importance of LED and its technology  
progress... I still have 1st Nichia blue LED of NA in my room (a gift  
- key chain)  The true blue.... i just point out so far there is no  
std (at least not like IPC std), point out it is rather difficult in  
current environment to get high quality std (the best you can get is  
above average by vote... so most of vendor can comply... ).  As a  
user, in good old days, you write environmental requirements (temp  
range stability, beam profile, etc.etc.), I don't think  you can do  
that for current LED industry (was involved  LED array in mid 90s for  
aviation application... night vision compatible, high density die  
array... not individual LED packaged).. if I sent out same spec out,  
most of the vendor (if they don't  know you personally, or you don't  
deal with their top RD dept), you possibly will be told to jump the  
lake... ;-).  I should keep open minded and wait until std come  
out... best of luck.
jk
On Nov 9, 2017, at 6:05 PM, SALA GABRIELE wrote:

> Totally agree,
> 	in the last 15 years we had at least three generations of LED's  
> technologies. For instance SSL (Solid State Ligthing) Tech is  
> growing so fast day by day.
> By now, let's follow at least the Guide Lines provided by  
> Manufacturers even if some of them Classify certain LED  MSL-5  
> (very conservative way....)
>
> -----Messaggio originale-----
> Da: TechNet [mailto:[log in to unmask]] Per conto di Stadem, Richard D
> Inviato: gioved“ 9 novembre 2017 23:04
> A: [log in to unmask]
> Oggetto: Re: [TN] R: [TN] Moisture-Sensitive PTH LEDs
>
> Sorry Joyce, but the LED usage within the industry is absolutely  
> huge, especially in military, avionics, tanks and land-based  
> military vehicles (think low-wattage, high lumen cool cockpit  
> lighting as an example), ships-military and commercial, as well as  
> industrial and residential (think lighting in refrigerators,  
> display freezers, stoves microwaves, everything!), and especially  
> the automotive and medical fields. It has exploded in the past few  
> years, and today the LED is probably the #1 most-used electronic  
> component, both PTH and SMT.
> I am sure there are many, many, "high" std process engineers who  
> have great interest in participating. I know a few that are "high"  
> all the time, in fact. :-) Yes, the old fashioned image of LEDs  
> being "small cheap version" certainly exists as well, but in  
> general LEDs are now available in all ranges of reliability and  
> applications and packaging styles.
> One of my client companies, Analog Technologies Corp, has certainly  
> seen that boom. It is absolutely huge, but we almost have to create  
> our own standards as we go along as it grew and is still growing  
> much faster than even the IPC and JEDEC can keep up.
>
> -----Original Message-----
> From: Yuan-chia Joyce Koo [mailto:[log in to unmask]]
> Sent: Thursday, November 09, 2017 2:23 PM
> To: TechNet E-Mail Forum; Stadem, Richard D
> Subject: Re: [TN] R: [TN] Moisture-Sensitive PTH LEDs
>
> the electronic std are based on ATT (bellcore), IBM and Motorola  
> and Mil std. you basically have majority std all set out by the  
> large players, and accepted by vendors and customer alike.  LED is  
> fragmented, you do have few large players, but many small cheap  
> version... even the testing are different.... not mention the heat  
> sink capability.  you will need more work to define std, and good  
> luck to get some "high" std process eng want... (you most likely  
> got out voted by smaller players... none of the large player's std  
> can be met by the smaller guys... go figure).  IMHO.
> On Nov 9, 2017, at 12:17 PM, Stadem, Richard D wrote:
>
>> I could not agree more.
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Ron Feyereisen
>> Sent: Thursday, November 09, 2017 10:11 AM
>> To: [log in to unmask]
>> Subject: Re: [TN] R: [TN] Moisture-Sensitive PTH LEDs
>>
>> There should be an entire new standard pertaining only to LED
>> technology- regarding moisture, ESD, application temps, and other
>> unique issues with SSL design. No longer a fad, LEDs are prolific in
>> our lives and their use is expanding rapidly every year. It's amazing
>> that the LED arena has gone without standardization for this long.
>>
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D
>> Sent: Wednesday, November 08, 2017 3:34 PM
>> To: [log in to unmask]
>> Subject: Re: [TN] R: [TN] Moisture-Sensitive PTH LEDs
>>
>> That is good to know, but then J-STD-033 and 020 should reference J-
>> STD-075, and vice versa.
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of SALA GABRIELE
>> Sent: Wednesday, November 08, 2017 2:46 PM
>> To: [log in to unmask]
>> Subject: [TN] R: [TN] Moisture-Sensitive PTH LEDs
>>
>> Let's not forget the IPC/J-STD-033 is a : Standard for Handling,
>> Packing, Shipping and Use of Moisture/Reßow Sensitive Surface Mount
>> Devices
>>
>> We are now talking about THT LED components (for wave or manual
>> soldering)  not so easy packages to classify together with those
>> mentioned by IPC/J-STD-020  Moisture/Reflow Sensitivity  
>> Classification
>> for Non hermetic Surface Mount Devices
>>
>> Joint Standardization  and Component Manufacturers and Users should
>> pursue may be the activities in order to improve IPC/J-STD-075
>> (2008) Classification of Non IC Electronic Components for Assembly
>> Processes, and may be include those strange components (THT LEDs, SMD
>> LEDS, SMD Tantalum Cap, etc ) declared MSD....
>>
>> Today J-STD-075 picks up where J-STD-020 left off by providing test
>> methods to classify worst-case thermal process limitations for
>> electronic components.
>>
>>
>>
>> -----Messaggio originale-----
>> Da: TechNet [mailto:[log in to unmask]] Per conto di Ron Feyereisen
>> Inviato: mercoled“ 8 novembre 2017 21:08
>> A: [log in to unmask]
>> Oggetto: Re: [TN] Moisture-Sensitive PTH LEDs
>>
>> Done and sent. There's a convenient electronic version of the form
>> available on the ipc.org website.
>>
>> Thanks for the suggestion!
>>
>> Ron
>>
>> -----Original Message-----
>> From: Stadem, Richard D [mailto:[log in to unmask]]
>> Sent: Wednesday, November 08, 2017 12:35 PM
>> To: TechNet E-Mail Forum; Ron Feyereisen
>> Subject: RE: [TN] Moisture-Sensitive PTH LEDs
>>
>> Excellent post, absolutely spot on!
>> On the back page of J-STD-033 is the form for suggesting improvements
>> to the Standards. Fill it out and send it in.
>> IPC, are you listening?
>> dean
>>
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Ron Feyereisen
>> Sent: Wednesday, November 08, 2017 12:02 PM
>> To: [log in to unmask]
>> Subject: Re: [TN] Moisture-Sensitive PTH LEDs
>>
>> We wish to avoid having to bake brand new LEDs since the labor and
>> time involved to do so is not covered in the quote for the job- yet.
>> Plus, the manufacturer should ensure that their LEDs are free of
>> moisture at the time of receipt. We will then ensure that our own
>> handling of the LEDs follows industry standards such as J- STD-033.
>> Also, the suggested bake time, per the datasheet, is 30 hrs!
>>
>> I'm surprised to see that J-STD-033 hasn't been updated to include
>> through-hole components since now days it's becoming common that even
>> some through-hole components are very moisture-sensitive. In years
>> past when parts were larger, it wasn't much of an issue, hence the
>> SMD-only J-STD-033 standard. This manufacturer refusing to label and
>> MBB pack their MSL 4-like sensitive LEDs only because they are not
>> SMDs is not helping anyone. Without saying who they are, they are a
>> popular LED manufacturer- so beware!
>>
>>
>> Thanks to everyone for their helpful comments!
>>
>> Ron
>>
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Larry Dzaugis
>> Sent: Wednesday, November 08, 2017 11:17 AM
>> To: [log in to unmask]
>> Subject: Re: [TN] Moisture-Sensitive PTH LEDs
>>
>> Good luck getting the manufacture to label and package correctly.
>>
>> In the mean time, add bake out to the receiving inspection
>> instructions and seal in a MBB properly labeled.
>> You will be able to use them with the same SMD procedures  
>> currently in
>> place.
>> Easier to square it away at receipt rather than when pulling from
>> stock.
>>
>>
>>
>> On Wed, Nov 8, 2017 at 12:05 PM, Stadem, Richard D
>> <[log in to unmask]
>>> wrote:
>>
>>> I have not seen exactly this issue, but have seen other PTH
>>> components that were actually SMDs embedded within a through-hole
>>> package, very similar to your situation, but not LEDs.
>>> I not only reviewed J-STD-033, but also J-STD-020 which is the
>>> methods used for moisture sensitivity classification.
>>> J-STD-020, like J-STD-033, starts off saying that the methods used
>>> are for classification of SMT devices. No mention is made of PTH
>>> devices.
>>> I do not know of any industry standard that addresses either the
>>> classification or handling of non-SMT Moisture Sensitive parts,  
>>> but I
>>> do believe it should be addressed.
>>> If any such IPC or JEDEC standards DO exist for PTH parts, then
>>> references should be made within both J-STD-020 and J-STD-033
>>> directing the user towards them.
>>> For some components such as DIP ICs that are also commonly formed in
>>> gull-wing configuration for SMT use, for example, the component
>>> manufacturer should comply and label them accordingly if in fact  
>>> they
>>> are MSDs from a reflow standpoint, even if they are not  
>>> "technically"
>>> required to do so. Ditto with components that are actually flip-chip
>>> LEDs encapsulated inside of a lens on a PTH platform.
>>> But no matter what, PTH or SMT, if the parts are moisture sensitive,
>>> they should be classified and labeled as such to meet the intent of
>>> the standards.
>>>
>>> Because parts from one manufacturer may be MSDs of a Level 3 and  
>>> from
>>> a different manufacturer Level 5a, and from yet another manufacturer
>>> not MSDs at all, there is no way any MRP system can keep track of
>>> them if they are not labeled as MSDs by the manufacturer. As a
>>> result, for many companies the only means of notification that any
>>> package contains Moisture Sensitive parts is if there is an MSD  
>>> label
>>> on the outside of the Moisture Barrier Bag and packaged to meet the
>>> dryness requirement. This is common sense, and any reputable
>>> component manufacturer would have an implied responsibility to  
>>> follow
>>> that best practice no matter what the package type or assembly
>>> process possibly used, wave, selective, manual, or reflow.
>>>
>>> If they require dry handling and bake-out to survive the assembly
>>> process, they should be labeled accordingly.
>>>
>>> -----Original Message-----
>>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Ron Feyereisen
>>> Sent: Wednesday, November 08, 2017 9:06 AM
>>> To: [log in to unmask]
>>> Subject: [TN] Moisture-Sensitive PTH LEDs
>>>
>>> Hi Technetters,
>>>
>>> Just wondering if anyone has come across this issue-
>>>
>>> We're being asked to Wave process assemblies that use small 3mm
>>> through-hole LEDs. We started to see a high failure rate during
>>> product testing of these LEDs and the root cause investigation found
>>> that, after verifying that the profile was per recommended, the LEDs
>>> are stated on the datasheet as being moisture-sensitive and require
>>> baking after 72 hrs being out of the original bulk poly bag
>>> packaging.
>>> (not a moisture barrier bag)
>>>
>>> The manufacturer's original packaging is insufficient to protect
>>> against moisture absorption since it's not a MBB, does not state the
>>> LEDs are moisture-sensitive and do not contain desiccant nor a
>>> humidity indicator card. Since J-STD-033 only refers to surface  
>>> mount
>>> devices, what other industry controls are in place to identify
>>> moisture-sensitive through-hole devices such as these? The 72 hour
>>> requirement should be handled as MSL 4 but the manufacturer is  
>>> saying
>>> that it only applies to SMDs for the marking and packaging. We do  
>>> not
>>> want to have to bake these LEDs each time we run the assy, as  
>>> well as
>>> mitigating defects.
>>>
>>> Any suggestions for recourse on this issue? It'll be much
>>> appreciated!
>>>
>>> Thanks,
>>> Ron
>>>
>>
>>
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