# SDRAM chips and other memory chips like those



## Paige (Apr 29, 2007)

If you were to cruch SDRAM (?) memory chips and those like them into dust and them recovered whatever is inside of them, would you have anything which was worth the effort?

I know stripping the gold from the edge would have some worth, but what about is in those chips?


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## lazersteve (Apr 29, 2007)

Paige,

You've asked another excellent question. In an effort to answer your question I have inadvertently discovered an interesting fact that was unknown to me. I've always known the black integrated circuits (ICs) contained silver, gold, and pgms. I've never processed any because of the required crushing and assumed minimal yields. Today you have provided me with some new information.

I decided to run a few ICs thru a heavy duty paper shredder (Fellows Model PS-80). This shredder is mean, it can shred up to 12 sheets of paper at one time. Anyway, I started feeding ICs from various boards into it to get an idea of just what was in them. I shredded about a pound of them into bits about 1/8 across and smaller. I looked down into the bin and noticed something unusal. One of the IC pieces was attached to a small circuit board (?). This is very unusual for plastic pak ICs. What makes this one of those eureka moments is that the circuit board had gold traces all over it!. Luckily the gold traces still had a chunk of the plastic package attached to it and I saw a portion of the manufactures logo. I immeadiately recognized the logo and searched out several other IC's from the same manufacturer. 

Here's what I discovered:







This is a photo of one of the source ICs and another which went thru the shredder (I cleared the bin and shredded a single IC for the photo). So it looks like these IC do still have surprises inside for us scrap hounds. I've decided to check several individual types of the same generation of IC to determine if any others have this kind of hidden treasure inside. I'll keep the forum posted. The chip in the picture comes from an old 14.4 ISA Modem. It just so happens that I bought over three hundred pounds of these modems from a guy on ebay last year!

I'll post a follow up when I get some average yields for this type of scrap.

Cheers,

Steve


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## goldsilverpro (Apr 29, 2007)

That part really was loaded. Do I see a hybrid circuit in there? Do you think the shredder will hold up? It sure did a perfect job on the part. I bet it was really noisy.


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## lazersteve (Apr 29, 2007)

goldsilverpro said:


> I bet it was really noisy



My wife said she thought a giant rat was upstairs chewing thru the wall. She was out front doing yard work!

Steve


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## goldsilverpro (Apr 29, 2007)

I'm still laughing.


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## lazersteve (Apr 29, 2007)

goldsilverpro said:


> Do I see a hybrid circuit in there?



Chris,

You are correct. This is one oddball IC configuration. Typically hybrids are mounted in an exposed state or sealed in a single in-line package (SIP). I never knew they put hybrids in plastic quad packs! I've been hands on in the electronics industry for nearly 20 years and have never seen this type of configuration. I'm hoping to find more surprises like this one in my scrap pile. The most unique aspect of this little bugger is that the gold looks to be plated onto the substrate directly. I also can make out a perimeter of what appears to be Pd or Ag on the ground plane. Definitely a great find! Thanks Paige ! :wink: 

Steve


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## goldsilverpro (Apr 29, 2007)

Is the hybrid a thin film (shiny metals) or thick film (matte) circuit.


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## lazersteve (Apr 29, 2007)

It appears to be a copper ground plane with a silver or palladium perimeter. On this is a small fiber circuit board with the gold traces. Very unusual for 1995. The core is mounted on the ground plane and has gold wire interconnects to the internal circuit board.


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## mike.fortin (May 1, 2007)

Steve--I read your post with photo about putting ICs thru a heavy duty paper shredder (Fellows Model PS-80). Have you ever found any shredder which would reduce monitor housings to more manageable pieces for disposal? You or anyone use a wood chipper do the job? Thanks. Mike Fortin


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## lazersteve (May 1, 2007)

Mike,

I just take mine to the dump when I get a truck load.

Never tried using a chipper.

Steve


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## lazersteve (May 4, 2007)

Hello Everyone,

I started rounding up some of my modem chips that are the hybrid types as pictured above. I did a few *controlled* crushings with a sledge hammer to get a better look at what I was dealing with in these chips. Here's what I found:







I started pulling the chips from the modems and managed to gather over two pounds of them in less than 10 minutes.

If anyone else finds chips of similar construction please post pictures along with the type of chip and part number on the chip. 

From the looks of these things they are going to put out gold, silver, and possibly even palladium.

Thanks,

Steve


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## zauggart (Mar 17, 2008)

hi there 
i just took apart a chip that says rockwell 93 and it too is the same inside as the rockwell 95 in the pic above
thanks
Ian


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## silversaddle1 (Mar 20, 2008)

Hey guys, I too just did a Rockwell chip and found the gold board too. Here's a quick way to open them up. Place them in a vise, on edge, not flat, and turn them until they break. The three I did popped right open and the gold was right there for the takin!


Thanks!


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## Scott2357 (Mar 28, 2008)

Newbie here.

Did I miss the yield report somewhere?

Also, I've been looking for average yield for CPUs, etc. Can someone point me to the data?

Thanks.


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## alpha1 (May 1, 2008)

Hello, guys.
What I found is that all Rockwell modem chips which are about 2 mm thick have such gold.
I crushed a few chips from 14,4Kbps to 33,6Kbps.


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## Harold_V (May 2, 2008)

lazersteve said:


> goldsilverpro said:
> 
> 
> > I also can make out a perimeter of what appears to be Pd or Ag on the ground plane. Definitely a great find! Thanks Paige ! :wink:
> ...



Yet another example of why e scrap is processed by incineration and furnace by the "big boys". What better way to extract all the values? It's a damned shame a safe method isn't devised that would allow home refiners to incinerate this stuff. It could spell the difference between spinning one's wheels and making a decent profit. 

Harold


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## Rag and Bone (May 2, 2008)

"It's a damned shame a safe method isn't devised that would allow home refiners to incinerate this stuff"

I hear ya brother! I would be happy with a few cubic feet of incinerator space and proper fume scrubbing and filter to catch values.


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## flankdrive04 (Jun 11, 2008)

goldsilverpro said:


> That part really was loaded. Do I see a hybrid circuit in there? Do you think the shredder will hold up? It sure did a perfect job on the part. I bet it was really noisy.




NICE!!


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## GeeDub (Feb 8, 2009)

I have been thinking for years, about getting one of Keene's centrifugal crushers for chips:

http://www.keeneeng.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=RC1&Category_Code=RC

Anyone out there ever try this thing?


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## wop1969 (Apr 1, 2009)

I have been exploring chips and have some good findings.
The first pic is the rockwell 95, and once more full of gold.
the second one and third chips have gold on the copper traces but only one one side so dont let it fool you if you see copper on a trace when a chip is first opened.


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## wop1969 (Apr 1, 2009)

This Chip I wanted to know if anyone has seen this in a chip, it has a purple coating ??


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## 61 silverman (May 19, 2009)

Rockwell Chips= 1992 Made in Japan 1993-1998 made in MEXICO latest date I have found..


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## jaun (May 30, 2009)

Some nice gold wires in the top (plastic) on the left.
Where the silica chip is.
They used gold wire to connect the chip to the leads, and cast the (plastic) over it.
The gold wire is in the (plastic)
What is the ( black plastic) doe any body know?
I think it’s called epoxy or something.

It would be nice to find something that dissolves the (plastic) and leave only the gold wires.


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## goldsilverpro (May 30, 2009)

If they are gold, I would guess that the value of the bonding wires on that part would range from $0.06 - $0.20, depending on the length and diameter.

Incineration would liberate the wires.

THESE NUMBERS ARE WRONG. SEE MY CORRECTION BELOW!!


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## jaun (May 30, 2009)

Is that per chip, pound or kg?


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## goldsilverpro (May 30, 2009)

I would say per unit. There are 64 leads. If each of the bonding wires are 1/8" long, there is a total of 8" of wire. If 1/4" long, there is 16" total length.

Most gold bonding wire is either 0.001" or 0.0007" diameter. If .001", 1 troy oz will be 1 mile long = 63,360". If .0007", 1 tr.oz. = 2 miles = 126,720".

Therefore, @ a $950 gold market, using 8" of .0007" wire, the calculation is 
(8/126,720) x 950 = $0.06

*CORRECTION:* I made an error. There seems to be 32 leads. Cut my numbers in half = about $.03 to $.12 each. Sorry. My math is OK but I never learned to count.

CORRECTION #2 I really screwed up on this thread. 1 tr oz of .001" 99999 gold wire would be 2 miles long instead of 1 mile. One tr oz of .0007" wire would be 4 miles long. This would reduce the bonding wire value of one of these parts to between $.015 and $.06. Of course, there are often other gold values in these parts besides the bonding wires.


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## jaun (May 30, 2009)

Wow! That’s not too bad, if you have a lot pc boards full of ic’s and flat packs. 
Like you said incineration would be the way to go.


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## 61 silverman (Jun 2, 2009)

The only boards that I have found the ROCKWELL chips both encased and surface mount have been internet connect cards , W/ phone line connection's .
mark sorry about the blurry pic.


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## golddigger2 (Jul 18, 2012)

Anyone ever think of using a garden shredder for flat packs just sling them in the top put a plastic bag over the outlet and turn on the juice


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## Harold_V (Jul 19, 2012)

golddigger2 said:


> Anyone ever think of using a garden shredder for flat packs just sling them in the top put a plastic bag over the outlet and turn on the juice


Blink!
Blink!

Could it be you have overlooked the fact that the ultimate goal is to reclaim the values, not one of losing them? I don't see your suggestion as a viable solution, but I do see it as a way to destroy the garden shredder. 

I'd be hard pressed to endorse the idea, although, perhaps, you can enlighten me so I can understand your logic. Perhaps I'm missing something. 

Harold


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## NoIdea (Jul 19, 2012)

Trust me when i say.... "it don't work", what you will end up with is alot of chipped chips and one messed up shredder, end of story :lol: 

Deano


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## 924T (Aug 16, 2012)

I was overtaken by curiosity after reading this thread, so I emailed Keene Engineering and asked them
if they thought their 400mph crusher would do the job on flatpacks.

Mark Keene replied the next day: "If you can smash a chip with a hammer and it shatters the RC1 should work fine. The chips have to be somewhat brittle in order for the RC1 to work."

I then sent him dimensions of the various sizes of flatpacks, and his reply was: 
"It sounds like it might work. If you can send me a few samples I might be able to test one."

So, the question of whether the Keene RC-1 400mph smasher will work on flatpack i.c. chips can
be answered------------------I'm still putting together my first kilo of quads----------does anybody have
a bunch sitting around, that could send a pound to Keene for testing?

If not, I'll send Keene what I've gathered so far, and post the results.

Cheers,

Mike


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