in Search
Untitled Page

ARCHIVED FORUM -- April 2007 to March 2012
READ ONLY FORUM

This is the first Archived Forum which was active between 17th April 2007 and 1st March February 2012

 

Latest post 11-06-2011 7:14 PM by satmonster321. 1 replies.
Page 1 of 1 (2 items)
Sort Posts: Previous Next
  • 09-22-2011 1:41 PM

    SMD LEDs Storage/Moisture Sensitivity

    Hi There,

    I am getting my stuff together to do some display rebuilding in my 8000 and 6000 Beomasters (thanks for all the great workbench posts explaining how to do it!). Am still waiting for my hot air rework station, but I just received the SMD LEDs and some SMD prototyping boards for practicing. After opening the Newark package, I could not help seeing large warning labels informing me that my new LEDs are "moisture sensitivity level 2" and "2a", which means that they must be soldered within 1 year ("2") and 4 weeks ("2a") after opening of the sealed package (otherwise the "popcorn" effect is to happen during soldering when water inside the package expands and cracks the device).

    Since I bought a bunch more than I need right now (I am also expecting to kill a few during practice...;-) I am naturally wondering about how to store them properly.

    I am considering putting them in mason jars with silica desiccant bags and evacuating the jars with my food storage vacuum pump. I was wondering if that is a good idea, or if there is a better method (or should one care at all about this moisture business...;-).

    Thanks much in advance for any insight!

    Rudy

  • 11-06-2011 7:14 PM In reply to

    Re: SMD LEDs Storage/Moisture Sensitivity

    Hello Rudy,

    the parts you want to store cannot have contact with air (humidity) until they will be soldered. In other words, keep them dry in a bag or other package that not allow the contact with the air.

    Even if the parts already had contact with the humid air, it is possible to "dry" them through slow backing in hot air. I dont remember which Jedec Standard describes how long and with which temperature they should be backed/reconditioned. But you get more info if you search for  IPC/JEDEC J-STD-20 MSL Classifications

    Regards

    satmonster321

Page 1 of 1 (2 items)