I bought some AM186 and AM188 IC's. The caution note on the bag says if I use infered or vaper-phase reflow, after I open the bag, I need to install the IC's in 168 hours, if I don't store them in places with relative humidity of <20% after opening. Otherwise I need to bake them (192 hours at 40C and 5% or 24 hours at 125C). I think this requirement is hard to understand. If they are not wet, I can't see how a little bit humidity would distroy them when I reflow them in the oven. Can somebody enlighten me? Thank you. vax, 9000
bake the IC before mounting?
Started by ●January 28, 2005
Reply by ●January 29, 20052005-01-29
On Fri, 28 Jan 2005 22:52:21 -0500, the renowned "vax, 9000" <vax9000@gmail.com> wrote:>I bought some AM186 and AM188 IC's. The caution note on the bag says if I >use infered or vaper-phase reflow, after I open the bag, I need to install >the IC's in 168 hours, if I don't store them in places with relative >humidity of <20% after opening. Otherwise I need to bake them (192 hours at >40C and 5% or 24 hours at 125C). I think this requirement is hard to >understand. If they are not wet, I can't see how a little bit humidity >would distroy them when I reflow them in the oven. Can somebody enlighten >me? Thank you. > >vax, 9000There is a bit of moisture in popcorn kernels. Same thing. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Reply by ●January 29, 20052005-01-29
On Fri, 28 Jan 2005 22:52:21 -0500, "vax, 9000" <vax9000@gmail.com> wrote:>I bought some AM186 and AM188 IC's. The caution note on the bag says if I >use infered or vaper-phase reflow, after I open the bag, I need to install >the IC's in 168 hours, if I don't store them in places with relative >humidity of <20% after opening. Otherwise I need to bake them (192 hours at >40C and 5% or 24 hours at 125C). I think this requirement is hard to >understand. If they are not wet, I can't see how a little bit humidity >would distroy them when I reflow them in the oven. Can somebody enlighten >me? Thank you.Google for the terms "popcorn reflow humidity" or similar for some lengthy explanations and a few nice pictures. -- Rich Webb Norfolk, VA
Reply by ●January 29, 20052005-01-29
Spehro Pefhany wrote:> On Fri, 28 Jan 2005 22:52:21 -0500, the renowned "vax, 9000" > <vax9000@gmail.com> wrote: > > >>I bought some AM186 and AM188 IC's. The caution note on the bag says if I >>use infered or vaper-phase reflow, after I open the bag, I need to install >>the IC's in 168 hours, if I don't store them in places with relative >>humidity of <20% after opening. Otherwise I need to bake them (192 hours at >>40C and 5% or 24 hours at 125C). I think this requirement is hard to >>understand. If they are not wet, I can't see how a little bit humidity >>would distroy them when I reflow them in the oven. Can somebody enlighten >>me? Thank you. >> >>vax, 9000 > > > There is a bit of moisture in popcorn kernels. Same thing. >Except the AM186 won't taste as good, and you will probably have significantly more old maids. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com
Reply by ●January 29, 20052005-01-29
Hi, Every device has a moisture sensitivity level ( MSL ).... This outlines how long the device can be out of it's foil package, before it needs to be re-baked, to dry out the device. A MSL of 1 means the device can be used without any baking, no matter how long it was out of the foil packet, not many devices have an MSL of 1. The MSL rating is given to a particular device ( or probably more correctly to a particular package ) after testing, ie the device is soaked in a particular relative humidity, then it is sent through a re-flow process, then the packaged is analysed for any changes in the structure. Optical packages are particularly sensitive to moisture, this is cause they don't have any quarts in the plastic. LEDs are know to some times "pop" due to the moisture expanding in the material. In saying all that, you would only typically see a very small fall out due to MSL problems. "vax, 9000" <vax9000@gmail.com> wrote in message news:ctf11i$t7q$1@charm.magnus.acs.ohio-state.edu...> I bought some AM186 and AM188 IC's. The caution note on the bag says if I > use infered or vaper-phase reflow, after I open the bag, I need to install > the IC's in 168 hours, if I don't store them in places with relative > humidity of <20% after opening. Otherwise I need to bake them (192 hoursat> 40C and 5% or 24 hours at 125C). I think this requirement is hard to > understand. If they are not wet, I can't see how a little bit humidity > would distroy them when I reflow them in the oven. Can somebody enlighten > me? Thank you. > > vax, 9000 >
Reply by ●January 29, 20052005-01-29
Friendly amendment Usually the popcorn effect does not show up as a failure right away but as corrosion months or years later. ALso these small cracks can often not be seen without a microscope. For any kind of product that you will be liable for, just make sure you use the open package in 168h Schwob David Powell wrote:> Hi, > > Every device has a moisture sensitivity level ( MSL ).... Thisoutlines how> long the device can be out of it's foil package, before it needs tobe> re-baked, to dry out the device. > > A MSL of 1 means the device can be used without any baking, no matterhow> long it was out of the foil packet, not many devices have an MSL of1.> > The MSL rating is given to a particular device ( or probably morecorrectly> to a particular package ) after testing, ie the device is soaked in a > particular relative humidity, then it is sent through a re-flowprocess,> then the packaged is analysed for any changes in the structure. > > Optical packages are particularly sensitive to moisture, this iscause they> don't have any quarts in the plastic. LEDs are know to some times"pop" due> to the moisture expanding in the material. > > In saying all that, you would only typically see a very small fallout due> to MSL problems. > >If they are not wet, I can't see how a little bit humidity> > would distroy them when I reflow them in the oven. Can somebodyenlighten> > me? Thank you. > > > > vax, 9000 > >