Are all DIP style chips created equal?

[darshevo]

I have been saving ICs in a 5 gallon bucket and its getting on towards full finally. I did admittedly get a little lazy recently and ended up mixing a bunch of flat pack (not the fiber style) chips in with it that may need to be sorted out eventually.

My question is this: When taking the old style DIP ICs I see that some are a dull ceramic while others are plastic. Is there a difference in the way these chips would need to be processed? What about the flat packs I have mixed in? Will they need to be separated or do they process the same way as the DIP style ICs? (Crush then AP?)

-Lance

 

[Barren Realms 007]

You can do that, you might want to consider incineration first.

 

[dtectr]

You can do that, you might want to consider incineration first.

i have commercial document shredder, scrapped because of couple teeth 'claying ' up. Made to handle like 10 sheets at a time. if i shred, then incinerate, then A/P ...?

 

[Barren Realms 007]

You can do that, you might want to consider incineration first.

i have commercial document shredder, scrapped because of couple teeth 'claying ' up. Made to handle like 10 sheets at a time. if i shred, then incinerate, then A/P ...?

That sounds like a possible working game plane you have there if the shreader will eat the stuff up.

 

[goldsilverpro]

When taking the old style DIP ICs I see that some are a dull ceramic while others are plastic.

If the ceramic ones are the ones I am thinking about, they are made of 2 ceramic layers held together with a layer of glass. They will separate by heating to about 700-800F and then quenching in water. The glass shatters and they fall apart.

 

[lazersteve]

If you get the material milled to a fine powder you can pass a magnet over everything to pull any iron, then finish up with a HCl-Cl leech.

Steve

 

[Harold_V]

If you get the material milled to a fine powder you can pass a magnet over everything to pull any iron, then finish up with a HCl-Cl leech.

Steve

I would imagine that if there's any chance of even traces of values following the iron, it would be used in the stock pot.

That was my procedure when processing floor and bench sweeps from my customers. After incineration, everything was well abraded in a large mortar, then screened. Any iron that was then removed (using a magnet) was placed in the stock pot, where it served to cement values from low grade solutions. Any values that happened to be discarded with the iron were recovered when the stock pot acculations were processed.

Harold

 

[macfixer01]

When taking the old style DIP ICs I see that some are a dull ceramic while others are plastic.

If the ceramic ones are the ones I am thinking about, they are made of 2 ceramic layers held together with a layer of glass. They will separate by heating to about 700-800F and then quenching in water. The glass shatters and they fall apart.

Regarding the layered ceramic chips such as Mil Spec 54xx series TTL, EPROMS, or some older 8 bit processors... I'm not processing large amounts so I tend to use mechanical methods. Using an appropriately sized pair of end cutters at the glass juncture between the layers and giving a squeeze and a tug, I can pop off the ceramic cap to see whether there is visible gold under and around the silicon die. It works very easily on the narrower DIPs up to 20 pins, especially if soldered on. I can generally even do it with socketed chips if I apply some pressure to hold the chip in the socket and pry up and toward one end. Then for the soldered chips if I grip lower on the pins themselves and twist I can both break the pins loose from the lower ceramic wafer and take it all loose from the board in one motion. On wider chips such as 24, 28, or 40 pin ceramic DIPs I may have to grip toward one end and pry back toward the middle so the top cap breaks off in two pieces. Similarly I grip at the pins and twist to remove plastic DIPs from the board. Then I again use the end cutters to either split the chip horizontally above the pins or crack it vertically from one end to the middle. If I see a bit of visible gold on the inner tips of the pins or the metal strip holding the die it goes into a bag to save. Otherwise into the trash. I've never found any gold in the plastic DIPs that have the anodized heat spreaders inside. Once I do find gold the other chips on that board of the same brand, part#, and date code, are removed and saved also but don't need to be cracked open for checking. I can't say I've ever seen any gold on the pins from the ceramic chips either, I only save the lower ceramic wafer for the gold under the die. Pins on some of the plastic DIPs (Rarely on TI chips, but often on Motorola chips for example) have gold plated tips on the inside near the die. I think it would be a mistake to automatically sort them out magnetically and trash them since the silver colored pins are generally always magnetic. True this is all low grade material but something is better than nothing.

macfixer01

 

[dtectr]

Thanks for the pix & procedure - it helps me a lot.
BTW - how old are the machines these are coming off of? Are they primarily military electronics or other types, as well?
thanks again.
jordan

 

[macfixer01]

Thanks for the pix & procedure - it helps me a lot.
BTW - how old are the machines these are coming off of? Are they primarily military electronics or other types, as well?
thanks again.
jordan

These boards are from a German cotton mill according to the seller. The boards are heavily weathered but have a fancy script name on some of them which I believe says Shlafthorst. The chip date codes are mostly 1977. Almost every chip has been ceramic and a lot of them have the gold layer under the silicon die. Despite the weathering the gold on the connector pins appears to be very intact which bodes well. The flat pins on the connectors of this board can be pulled. Unfortunately the connectors of the smaller boards seem to be some sort of epoxy or resin cast around the round pins, so they're almost impossible to remove. It may require cutting them up or incineration. I had better hopes for these boards but you can only tell so much from bad pictures. I got a lot of nice boards from the same seller maybe 2 years ago from a different cotton mill that had long extended fork-like fingers on the board edges that were heavily plated. These boards he said had some extra dirt. It's more like they were caked with mud, and it must have some clay in it since washing with a hose didn't help remove much.

Those ceramic chips can be on any type of board really, they're just better suited to high temperature industrial environments. They cost more than plastic packaged DIPs, so aren't normally used in non military applications so much unless needed for reliability. EPROMs of course can be needed in lots of applications and since they require a UV window for erasure they're generally in a ceramic package. Then with mask-programmed ROMs, electrically-alterable or EAROMs, and finally Flash Ram, there is little reason to use ceramic packages anymore. Board real estate is a concern too so Flash or ROMs are often in square PLCC packages now.

macfixer01

 

[CHARLIE GREENLER]

Those are nice I have old mill spec IC,s too.I was wondering what is the palladium, gold , platnum and silver yeild in one pound of IC,s roughly speaking???

 

[goldsilverpro]

Those are nice I have old mill spec IC,s too.I was wondering what is the palladium, gold , platnum and silver yeild in one pound of IC,s roughly speaking???

If your talking about the ceramic DIPs above, I would guess $10-$12/pound for the small ones, as in the photos - assuming you break them open and see gold. Sometimes, you will see silver instead and they aren't worth much. No Pt or Pd that I've seen.

Charlie, you sure have Pt and Pd on the brain. Generally, they are rare in electronic scrap, except for the Pd in chip capacitors.

 

[jimdoc]

Charlie, you sure have Pt and Pd on the brain.

Don't forget rhodium too.