Do you think China can supply authentic 1980's 4164 64Kx1 DRAM chips? - Page 1
Forum section: electronics / general

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 11, 2021, 07:21:05 pm
content: https://www.aliexpress.com/item/32502628342.html?spm=a2g0s.9042311.0.0.26d74c4djJ9h5FHard to tell from just their "glamour shot" of a generic vendor-less chip.I ordered some for fun and what I got doesn't look right to me. I need to dig out my socketed C64 to test these chips later.On the left is a real TI 41256 from my hoard. It's not the same type but the markings and package details are different from the Ali Express special on the right.I know the pics are terrible, but the 1980s part has printed or silkscreened markings, but the Ali part is laser etched, I can see the depth of the markings,Did they laser-etch chips like this in the 1980s?

author: wraper
author_rank: Unknown
timestamp: December 11, 2021, 07:32:54 pm
content: It's an old IC pulled from e-waste with marking removed and relabeled. Likely some 4164 from other manufacturer.

author: wraper
author_rank: Unknown
timestamp: December 11, 2021, 07:38:46 pm
content: It's marked Japan on the bottom and looks similar to Mitsubishi.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 11, 2021, 07:48:14 pm
content: When I visit my Dad I'll stick a chip on the bench vise and crack the package open and see what pops out.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: December 11, 2021, 07:59:53 pm
content: Laser-etched? From the '90's? Very suspicious.

author: strawberry
author_rank: Super Contributor
timestamp: December 11, 2021, 08:17:08 pm
content: in listing description some Russian USSR calculator to appeal to russian buyers??you could see solder dip if weldedmost likely some similar/rejected china made chip, as china stop waste imports some years ago

author: james_s
author_rank: Super Contributor
timestamp: December 11, 2021, 08:30:00 pm
content: They do this all the time. They take old salvaged parts, clean them up, sand the top down and re-mark them as some reputable brand. Sometimes the parts are at least what they say they are, other times they are whatever random IC in the right package they had laying around.

author: MadTux
author_rank: Frequent Contributor
timestamp: December 11, 2021, 09:14:41 pm
content: Very common with power electronics in Isotop package, too.If it behaves like a mosfet, relabel it to whatever device you want, the one that sells the best.Very likely the same with vintage parts, if the package fits, the laser will write anything onto it.If it somehow has the right pinout and stores 64Kx1, even better, but not strictly necessary.Highly doubt china stopped ewaste imports, otherwise the recycling markets at Shenzhen would dry up very quickly.Also do you really think anyone still makes 64kx8 DRAM???

author: magic
author_rank: Super Contributor
timestamp: December 11, 2021, 09:27:34 pm
content: Not sure if the TI logo is completely right.Pull out a DMM and look for input clamping diodes to power supply pins. Compare between the two chips.

author: amyk
author_rank: Super Contributor
timestamp: December 11, 2021, 10:34:51 pm
content: Quote from: MadTux on December 11, 2021, 09:14:41 pmIt's 64kx1, but yes... look for NTE4164.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 11, 2021, 11:03:25 pm
content: Quote from: MadTux on December 11, 2021, 09:14:41 pmNot at all. I knew they must be either fakes or at best, pulls or some weird giant lot of chips that traversed time somehow.

author: retiredfeline
author_rank: Frequent Contributor
timestamp: December 12, 2021, 12:20:11 am
content: Hmm, maybe my pile of 4164 and 41256 pulls from old PCs are worth something on eBay? 🤔

author: james_s
author_rank: Super Contributor
timestamp: December 12, 2021, 07:04:24 am
content: Quote from: amyk on December 11, 2021, 10:34:51 pmNTE doesn't make them and never did, they're just re-marks too, however NTE parts are legitimate remarks that are trustworthy if often overpriced.

author: VK3DRB
author_rank: Super Contributor
timestamp: December 12, 2021, 10:59:17 am
content: No.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 12, 2021, 03:36:29 pm
content: Quote from: VK3DRB on December 12, 2021, 10:59:17 amPretty much.Oh well, a $3 lesson learned.

author: wraper
author_rank: Unknown
timestamp: December 12, 2021, 03:42:39 pm
content: The answer is actually yes if you want to buy genuine used ICs. Like these, cheaper and not relabeled.https://www.aliexpress.com/item/4000416859913.html

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 12, 2021, 03:52:12 pm
content: Quote from: wraper on December 12, 2021, 03:42:39 pmHave you ordered any from them? I'm willing to risk another $3 for science!

author: wraper
author_rank: Unknown
timestamp: December 12, 2021, 05:06:25 pm
content: Quote from: Alex Eisenhut on December 12, 2021, 03:52:12 pmNo, but YMMV with any Chinese component seller. Even if you bought a genuine part once, does not guarantee you will get the same good part again. But considering that on the picture is not relabeled, you likely will receive such. You could contact the seller and ask for IC which is labeled with paint.

author: magic
author_rank: Super Contributor
timestamp: December 12, 2021, 07:07:37 pm
content: Not sure if it's a good idea because- the sellers may be dropshipping and not even know what they sell- if you really insist, the Chinese will supply you with anything you wishAs in, for example, military grade of parts which have never been produced in military grade. Sky is the limit.I also look for feedback with photographs of the delivered parts. It's not common, but if it's there, you know that at least at some point in the past given seller actually delivered legit ICs.

author: BrokenYugo
author_rank: Super Contributor
timestamp: December 12, 2021, 07:52:52 pm
content: My limited experience with buying vintage chips out of China is that if you really need it, place multiple orders and expect to get half the orders for free when the parts sold as NOS or unmolested pulls show up clearly solder dipped and/or remarked, in very not ESD safe packaging, nonfunctional, etc. I've gotten stuff that was NOS the best I could tell, in chip tubes, and I've gotten stuff that claimed NOS but showed up as solder dipped with mixed date codes, stacked up and wrapped in cling wrap. To be fair those chips do seem to work, but still, not cool.Ebay, or at least Ali with paypal, is preferred if you don't like throwing money away.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 14, 2021, 04:21:02 am
content: Well.... The size of the die seems to suggest a memory device of some kind! I think...This is just the lead-frame. The silicon is on the other side but didn't survive the vise.

author: james_s
author_rank: Super Contributor
timestamp: December 15, 2021, 04:37:55 am
content: You didn't test it first?It's probably a legitimate DRAM chip, it just isn't the brand printed on it and it isn't new.

author: all_repair
author_rank: Frequent Contributor
timestamp: December 15, 2021, 05:03:19 am
content: Don't talk about China, many here have enough used authenic 4164 to supply you. Put up a reverse bidding, and see how low offer you can get. If you are patience, wait and look out for free giveaway when people are clearing the lab.

author: rpiloverbd
author_rank: Regular Contributor
timestamp: December 15, 2021, 01:28:15 pm
content: To be honest, I do not find alliexpress to be a very reliable source. I have both good and bad experiences.

author: Canis Dirus Leidy
author_rank: Regular Contributor
timestamp: December 16, 2021, 03:00:00 am
content: Quote from: MadTux on December 11, 2021, 09:14:41 pmWell, don't know about DRAM, but some Chinese manufacturerstill make 8251 clone.

author: BrokenYugo
author_rank: Super Contributor
timestamp: December 16, 2021, 03:20:24 am
content: Also, why buy such a common low cost part from China? I'm seeing 4164 NOS from US and European sellers at reasonable prices. Not like we're after some old ASIC here where the Shenzhen special is often the only option or high dollar parts where the gamble may be worth it.e.g. (best deal I saw)https://www.ebay.com/itm/284216413617?epid=1923942526&hash=item422c9e4db1:g:Ak8AAOSwiONYNWN5Though I'd assume this stuff is about as slow as it came without digging up and translating a datasheet.Jameco also apparently has a source for it.https://www.jameco.com/z/4164-150-Major-Brands-IC-4164-150-DRAM-65-536-Bit-65-536x1-150ns-with-Page-Mode-DIP-16_41662.html

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 16, 2021, 04:30:56 am
content: I have hundreds of these chips from the '80s. Can't I just be curious?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: December 16, 2021, 07:09:12 pm
content: If you do a picture search for Guiyuhttps://duckduckgo.com/?q=Guiyu&t=h_&iax=images&ia=imagesThen you find pictures like below.Apparently labor is cheap enough to recycle almost anything.

author: Bud
author_rank: Super Contributor
timestamp: December 16, 2021, 07:39:14 pm
content: Well, then the answer to OP question is Yes.

author: Bassman59
author_rank: Super Contributor
timestamp: December 17, 2021, 06:53:23 pm
content: Quote from: Alex Eisenhut on December 11, 2021, 07:21:05 pmI don't know how many you need, but Jameco hasa few hundred, and my guess is that what Jameco is selling is genuine.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 21, 2021, 01:54:12 am
content: Well turns out 8 of the 10 chips I ordered seem to function correctly as 4164s as advertised. One went to Silicon Heaven and one measured short circuit.

author: james_s
author_rank: Super Contributor
timestamp: December 21, 2021, 07:25:19 am
content: That sounds about right for a random collection of old pulls.