Hello,
I have acquired a fairly comprehensive set of 7400 (BJT and CMOS) and CD4000 logic. The chips have been stored loose in plastic Akro Mils storage cabinets (non ESD safe plastic) in a non-temperature controlled warehouse. I would estimate many chips date back over 20 years, so I assume a majority have been in storage at least that long.
I would like to reorganize these devices and make them usable for a prototyping at work and home. However, I realize that the storage conditions of these chips are far less than optimal. Which brings me to my questions:
1. How likely is it that storage has damaged these ICs? I just don't know how these devices fare over such a long time in a warehouse that I'm sure reaches over 100F degrees in the summer, but probably not under 40F during the winter. As well as being stored in non-ESD safe containers.
2. How should I approach storage now to avoid damage in the future. I know the optimal solution would be purchase ESD safe bins. However, the costs are on me personally, and that is a very costly endeavor. Are the old hard plastic drawers prone to actually failing chips? On the work intensive side I had considered cutting ESD foam and lining the storage bins in layers, pressing the chip leads into the foam. But I want to know I'm being realistic about the necessity of such steps.
3. Still yet, I have access to metal cabinets and drawers. Are those a better choice (than plastic) for storage/use, I see opinions both ways on this. I simply don't know the precise details about static generative materials. For instance, is it ok to store IC's in statically generative plastic if you use proper ESD dissipation when removing them from the container?
Any insight into this issue is much appreciated, I'd just like some realistic options on keeping these parts safe.
Thanks in advance.
