Rules for Reusing Electronic Components

Phil
Welcome to Board Talk. This is Jim Hall and Phil Zarrow, the Assembly Brothers. Here to attempt to solve your process assembly problems. Jim, what's today's question?

Jim
Very interesting. What are the rules regarding reusing a component? If you remove a component from a circuit board, and the component is functional and not physically damaged, can it be reused on another circuit board? This comes from D.W.

The answer is maybe. Used components, or reused components, are very common. In fact, there's a whole industry to supply them. But the question is how reliable are they? Are they fully functional? And are they going to stand up and meet the product expectations for either the new or repaired product.

It really depends upon what you expect for the product the reused component is going into. If it's just a consumer product, not exposed to harsh conditions, that would be one thing.

Is the reused component going to be used to repair a piece of military avionics, which is a day-to-day thing for the military? And you can't get brand new parts for it. You have to use used parts. What tests do you do? There are laboratories that validate used or out-of-date old components and they put them through a variety of tests. Some test companies go as far as original manufacturer's specified tests.

So, yes, certainly you can reuse used components or scavenged components but making sure that they are reliable enough to meet the demands can be challenging. Particularly if it's going into a higher reliability product.

Phil
And there's also a concern with the level of operator skill of the folks who will be removing the components in the first place. 

The skill of the folks performing the removal and replacement process is paramount.

Jim
High temperatures do no good to any of the electronic components or materials, so limiting and the removal process, limiting it.

If you're talking about plastic ICs, make sure they are baked before being removed because those component are sure to be saturated from atmosphere moisture.

If you're going to use a hot air system that's going to heat the whole body of the component, you need to bake the board to remove the moisture or you're going to cause moisture sensitivity damage, popcorning, etc..

Even if you can't see it - remember you can have internal delamination and cracking in a component that you can only see through x-ray. Are you going to do that to the part before you reuse it?

Phil
Well, we hope that answers your question. This is Phil Zarrow and Jim Hall saying that whether you're replacing components or you're soldering them down for the first time - whatever you do ...

Jim
Don't solder like my brother!

Phil
Please don't solder like my brother!

Some other commenters have touched on it - but for industrial products the customer should always be notified that second hand components are used.

Per other comments, NADCAP AC7120D 24.1.f.P checks that reuse of components is only with authorization by the customer so anything aerospace or defense has restrictions.

We discussed the term "reuse" with an auditor recently and refined that a refinement to this term is when the same part is placed on the same board such as if a part was attached in the wrong orientation. Those circumstances are rework, not reuse.

Keep up the good work my "Brothers"!

Per other comments, NADCAP AC7120D 24.1.f.P checks that reuse of components is only with authorization by the customer so anything aerospace or defense has restrictions.

We discussed the term "reuse" with an auditor recently and refined that a refinement to this term is when the same part is placed on the same board such as if a part was attached in the wrong orientation. Those circumstances are rework, not reuse.

Keep up the good work my "Brothers"!

I suppose you are the product's owner or you have design authority on it. If so, yes you can reuse the components. Of course, reusing depends on type of component. I can tell you about BGA's. Some BGA's are very expensive components. When you remove a BGA from a PCB, if you have taken proper care during rework operation, most of times you can reuse them.

You need only do a tin-lead or lead-free reballing (if BGA is lead-free or not) and the component is almost a new one. Many others examples can be mentioned, like chip components or leaded ones, magnetics like transformers or toroid, etc. Also if you have a good test strategy after reworking I would say a BIG YES for reusing.

Missing from your discussion is any mention of Counterfeit Components and AS5553A. This is a VERY big issue in the Mil/Aero world and one of the obvious 'tells' of a counterfeit is a component that has been reworked.

You did not mention that it is illegal to reuse or resale a used part on a "new" product. One of my customers had to pay a big fine for pulling the PC boards out of class room demo units and putting them in a "new" cabinet and then selling the unit as new. One of their employees told on them.