What to do when you can only find the IC you need at Alibaba/Aliexpress? - Page 1
Forum section: electronics / beginners

author: Cyber Akuma
author_rank: Regular Contributor
timestamp: August 12, 2017, 04:04:17 pm
content: I don't want to purchase my ICs from these two places for obvious reasons. However, I have been trying to do some projects with some 20-30 year old game consoles, and this would require some rather old chips. Just about every major consumer distributor I could think of for the US (Mouser, Arrow, etc) I can't seem to find these parts at.... though surprise surprise Alibaba/Aliexpress have lots of them. Even more worrying, some of these sellers despite passing most of the "Tips to identify fakes on Ali"-style guides seemed to also be selling newer ICs I had been looking for for ridiculously cheap prices..... using blurry photos that don't seem to show any markings on the chips at all.Any suggestions what other US distributors I might be able to use for no longer manufactured ICs? Since I still don't know much about electronics, I wouldn't be able to spot a fake.... or even know if a fake is the reason my projects aren't working, so I really don't want to purchase from the Ali sites if I can avoid it. And again, since I am still pretty much a bigger, I am more or less following a guide, I wouldn't know how to use chips that are too different and would require extra components to make compatible with this old hardware.

author: FlyingHacker
author_rank: Frequent Contributor
timestamp: August 12, 2017, 04:08:51 pm
content: If it's for a personal project, and the price is cheap, just buy them and try them out. Not much sense in paying $10 for an IC you can get for 20cents if it is not going into some mission critical application.Many of the fakes work just fine. Of course you are not supporting the original R&D, but for an old chip I wouldn't be too worried about that.

author: edpalmer42
author_rank: Super Contributor
timestamp: August 12, 2017, 04:38:51 pm
content: Search for 'obsolete IC distributor'. There are U.S. based companies that specialize in this. But typically, they charge an arm and a leg for the products because there isn't a lot of competition and they think they've got you over a barrel. Either buy from them or replace the entire defective unit for, perhaps, many thousands of dollars.I was in this situation a few years ago. I needed a specialized IC that was single-source and discontinued years ago. A couple of the above-mentioned distributors had some, but at unattractive prices. I took a chance on an Aliexpress vendor since the price wasn't obscene and everything turned out good. The chips were original, NOS chips. I checked back a while ago and all the Aliexpress sources have dried up. Apparently they found a cache of these chips and now they're all gone.Ed

author: Cyber Akuma
author_rank: Regular Contributor
timestamp: August 12, 2017, 04:59:09 pm
content: Quote from: edpalmer42 on August 12, 2017, 04:38:51 pmHmm, the problem with this is that aren't the majority of these distrobutors made for businesses that would buy large amounts in bulk? I would only really need one.... maybe 5 or 10 at most just to expirement with if I can get them at an affordable price.Nearly all of the distrobutors don't have a price and require you to send them an inquiry for a quote.

author: stmdude
author_rank: Frequent Contributor
timestamp: August 12, 2017, 05:25:44 pm
content: I do repairs on old consoles, and I have yet to order anything from Aliwhatever..What kind of components are you looking for?For the standard chips (CPUs, DRAM, PIAs, ACIAs, etc), I order from Jameco.

author: Cyber Akuma
author_rank: Regular Contributor
timestamp: August 12, 2017, 05:45:45 pm
content: Quote from: stmdude on August 12, 2017, 05:25:44 pmI am actually looking to replace the SRAM chips used in some consoles and accessories with FRAM variants so I would not need a battery to keep the memory alive.There was already a post about someone who did that to their Sega Saturn (that's the old chip I am looking for actually -https://db-electronics.ca/2017/02/10/sega-saturn-internal-memory-mod-with-fram-no-battery-required/), and now I want to experiment to see if I can do it with the Sega CD RAM cartridges or even the Sega CD's internal memory itself.

author: andersm
author_rank: Super Contributor
timestamp: August 12, 2017, 06:18:10 pm
content: Quote from: Cyber Akuma on August 12, 2017, 05:45:45 pmHave a look at the parallel F-RAMs fromCypress.

author: edpalmer42
author_rank: Super Contributor
timestamp: August 12, 2017, 06:39:33 pm
content: Quote from: Cyber Akuma on August 12, 2017, 04:59:09 pmVery true. Sometimes they give either a minimum quantity or a minimum charge. But you might find one that will sell you one or two for a price that's somewhere between ridiculous and obscene. Remember, that's the market you're entering.Ed

author: Cyber Akuma
author_rank: Regular Contributor
timestamp: August 13, 2017, 10:52:48 pm
content: Quote from: andersm on August 12, 2017, 06:18:10 pmThe problem with those, other than price, is that while they seem to have an equivalent to the FM1808 for modifying my Saturn that way (FM18W08) and possibly an FRAM equivalent to my internal Sega CD's SRAM chip as well (FM16W08-SG), they don't have anything pin-compatible that I can use to replace the SRAM chip in my Sega CD's RAM cart, which was the main thing I wanted to attempt to modify. That cart used a SRAM chip that was 1Mbit, and can go up to 4Mbit, but anything 1Mbit and above from cypress are 44 pin TSOP II or 32 pin TSOP I packages, and I need a 32 pin SOP/SOIC package.

author: station240
author_rank: Unknown
timestamp: August 13, 2017, 11:21:39 pm
content: The issue isn't just fake ICs, some chinese sourced parts are simply recycled from e-waste, and haven't been tested to see if they work.So the chip would pass as legit, but not work.Given you're talking about SRAM/FRAM, perhaps less risk of fake ICs. It's high demand, ASICs and the like that are faked retro computer/console parts.Either make a test rig to test the ram before you install it, or use an IC socket so you can swap out suspect chips. They do make sockets for SOP/SOIC, but the prices can be high.Yes that does also mean getting more ICs that you need so you have spares.

author: andersm
author_rank: Super Contributor
timestamp: August 13, 2017, 11:35:04 pm
content: I'd say bite the bullet and make your own cart. Based on photos there's only address decoding logic and a buffer on them, so it won't be very difficult, and much easier than trying to deal with hard-to-find, obsolete parts.

author: Cyber Akuma
author_rank: Regular Contributor
timestamp: August 14, 2017, 12:08:51 am
content: Quote from: andersm on August 13, 2017, 11:35:04 pmI actually did find a guide on that:http://nfggames.com/forum2/index.php?topic=3383.0Issue is I don't know enough about electronics to fully figure out how do to it. I still need to fully research if those two FRAM chips I even decided on would be a viable substite or not. The guide for doing it to a Sega Saturn mentioned about some signals on the replacement FRAM chip operating on low when originally it was high, while other aspects canceled the operation if low, but I didn't fully understand that.Believe me, I would love to make my own, and far prefer it to dissecting an existing cartridge, but I lack the knowledge to do so.

author: CJay
author_rank: Super Contributor
timestamp: August 14, 2017, 08:04:37 am
content: Quote from: blueskull on August 14, 2017, 12:50:35 amThis is my gripe, seems so fashionable to jump on any mention of components from any Chinese source and scream 'fake' when in fact there are perfectly honest and reliable sellers who are providing damn good service and excellent prices.In my experience the overwhelming majority of parts I have bought have been absolutely fine, even the handful of parts I had that were fake (one from a British seller who guaranteed they were the real deal) I already knew there was a pretty good chance they'd be fake but bought them because there was a slim chance they were good parts re-marked from another manufacturer.

author: mzzj
author_rank: Super Contributor
timestamp: August 16, 2017, 01:10:24 pm
content: Quote from: CJay on August 14, 2017, 08:04:37 am2X this.Unless its some audiophoolery related part I wouldn't worry too much about ordering from aliexpress or china-ebay.IF the part is available from reputable sources(IE Digikey) that is my first option but I don't consider these various "obsolete IC distributors" any better than aliexpress.

author: FlyingHacker
author_rank: Frequent Contributor
timestamp: August 16, 2017, 05:31:22 pm
content: The only thing I will not buy from eBay is name-brand electrolytic caps. These are typically fake, and/or old. I want fresh caps from a known good supplier.eBay China is a very good source for no-name brand caps for experimenting, though.