Help id this IC - Page 1
Forum section: electronics / beginners

author: erolsansolo
author_rank: Contributor
timestamp: April 14, 2015, 10:04:08 am
content: I had a pack full of stuff delivered from a local supplier last week.Every item checked out OK except for this lot, which I couldnt find out what it was. I looked all over the web, probably im missing something.The IC in question arrived instead of a short reel of SOIC8 package 7812 regulator.The marking on it is: 8534 4ct c4n4. it bears the mark of TI.

author: atferrari
author_rank: Frequent Contributor
timestamp: April 14, 2015, 10:56:01 am
content: Two things come to mind upfront:Checking them against your order.Call the supplier.

author: erolsansolo
author_rank: Contributor
timestamp: April 14, 2015, 11:17:49 am
content: The SOIC8 7812 regulator is missing from the order. This 8534 came in its place. every other item checks out.I already called my supplier, they were also a little puzzled about the this IC when I told them it was 8534. They couldnt figure it out right away.They just said, "no problem, we are immediately sending you the SOIC8 7812 chips you ordered. You can keep the unknown ICs."

author: bktemp
author_rank: Super Contributor
timestamp: April 14, 2015, 11:34:33 am
content: TI has a part marking search:http://focus.ti.com/general/docs/partmarking/partmarkinghome.jspBut it does not give anything in SO8 for 8534 (or 85344).Therefore it looks like a custom IC or at least a custom part number.

author: Cliff Matthews
author_rank: Unknown
timestamp: April 14, 2015, 02:46:16 pm
content: SMPS have dual-diode schottky rectifiers with "CT" on the markings. The stripe over pins 1 and 8 (cathodes?..) and the "4CT" would lead me to think this could be polarity tested for diodes. If so, the TI logo might be present on some knock-off SOIC's.

author: zerorisers
author_rank: Regular Contributor
timestamp: April 14, 2015, 02:50:57 pm
content: Quote from: Cliff Matthews on April 14, 2015, 02:46:16 pmI have dealt with a chip the other day that looked similar with a stripe but it was a transformer driver. I will see if I can get the schematics and number later today. The number on the IC was not the real part number and the real number was shown on the schematic of the board. I can see if I can get in contact with a buddy of mine from TI and see if she knows anything that can help out here.

author: amyk
author_rank: Super Contributor
timestamp: April 14, 2015, 03:13:20 pm
content: Is that a datecode? Week 34, 1985?

author: bitwelder
author_rank: Super Contributor
timestamp: April 14, 2015, 04:04:01 pm
content: Have you checked if there is anything printed on the bottom side of the chip?

author: Fraser
author_rank: Super Contributor
timestamp: April 14, 2015, 04:52:12 pm
content: Not much help but.......http://www.aliexpress.com/store/product/Eight-feet-TI-8534-SOP8-patch/1299470_32311481502.html

author: erolsansolo
author_rank: Contributor
timestamp: April 14, 2015, 06:45:14 pm
content: When i first looked underside of the IC, there was a faint marking that i dismissed as i was obsessing about the front marking.Now under a microscope light, clearly this image raises more questions i think..

author: erolsansolo
author_rank: Contributor
timestamp: April 14, 2015, 06:49:11 pm
content: Quote from: Aurora on April 14, 2015, 04:52:12 pmWow, i didnt even come by on alibaba or aliexpress - good catch, tho as you say not much help

author: erolsansolo
author_rank: Contributor
timestamp: April 17, 2015, 04:45:34 pm
content: updateThe replacement reel for the missing 7812 SOICs arrived today, and guess what.. I received the same chip as before - 8534. Appearently it was 7812 all along. probably custom marked or knockoff.I will build a small test circuit to confirm.Just a heads up for anyone coming by the same chip.

author: Falcon69
author_rank: Super Contributor
timestamp: April 17, 2015, 04:47:23 pm
content: OR.....They sent the wrong one AGAIN!

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 17, 2015, 09:34:23 pm
content: And this is why I buy stuff from Farnell...

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 17, 2015, 09:52:50 pm
content: Quote from: smjcuk on April 17, 2015, 09:34:23 pmYea... because they never fuck up! *facepalm*

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 17, 2015, 10:05:41 pm
content: Actually I've never had a single problem with them in 20 years.

author: Dave
author_rank: Super Contributor
timestamp: April 18, 2015, 01:46:39 am
content: Consider yourself very lucky. They f*ck up my orders all the time and I don't even order that often.

author: erolsansolo
author_rank: Contributor
timestamp: April 18, 2015, 01:01:07 pm
content: Quote from: Falcon69 on April 17, 2015, 04:47:23 pmhahahh I hope not!if the chip blows up in the test circuit, then -

author: bookaboo
author_rank: Frequent Contributor
timestamp: April 18, 2015, 01:21:46 pm
content: Quote from: smjcuk on April 17, 2015, 10:05:41 pmQuote from: smjcuk on April 17, 2015, 10:05:41 pmI find them as reliable as you could reasonably expect, probably >99% of orders on time and correct.Reminds me of the time I found a random reel in the bottom of a box from Anglia (UK based components). At the time we didnt even do surface mount and the rest of the order matched the delivery note, so I did the honest thing and shipped it back without even looking what they were.In our next order we received an extra box with several boxes of very nice biscuits as a thank you, apparently the reel was worth >£7000. I was always known as having "spent" £7000 on biscuits.