SMD Component with Marking Code 3B 514 - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: August 20, 2023, 10:35:57 pm
content: Hello,I can't find what component is this on the attached picture. It has on it the Marking Code 3B 514.

author: amyk
author_rank: Super Contributor
timestamp: August 21, 2023, 01:52:49 am
content: Of all the possible 3B SOT-89 I've found, KIA431AF is a good guess, given that it goes to a reference voltage input and how it's connected makes sense for a 2.5V reference.

author: fzabkar
author_rank: Super Contributor
timestamp: August 21, 2023, 03:10:43 am
content: KIA431AFhttps://datasheet.lcsc.com/lcsc/1912111437_KEC-Semicon-KIA431AF-RTF-PC_C465009.pdfhttp://markingcodes.com/search/c/3bhttps://www.aliexpress.com/item/1005001906985299.htmlhttps://ae01.alicdn.com/kf/Ha38dc3efed7f40ce9f06ea24e3bb38cdY/10PCS-LOT-KIA431AF-RTF-P-KIA431AF-KIA431-3B-SOT89-New-original-In-Stock.jpg(photo)

author: 2X
author_rank: Frequent Contributor
timestamp: August 21, 2023, 05:21:10 am
content: Hello,the part number "KIA431AF" where did you find it? Because on the below smd marking codes sites didn't show me the "KIA431AF".http://www.smdmark.com/en-US/search/code?id=B3https://www.s-manuals.com/smd/b3http://markingcodes.com/search/c/B3

author: fzabkar
author_rank: Super Contributor
timestamp: August 21, 2023, 05:37:03 am
content: http://markingcodes.com/search/c/3bKeep clicking "NEXT" until CURRENT=6.BTW, your links are searching for B3, not 3B.

author: 2X
author_rank: Frequent Contributor
timestamp: August 21, 2023, 10:11:51 am
content: I apologize for my mistake... One more question... You search with order all the codes that shown on the site until you will find a voltage reference component or you use another method. Many thanks for your help.

author: fzabkar
author_rank: Super Contributor
timestamp: August 21, 2023, 05:08:54 pm
content: Quote from: 2X on August 21, 2023, 10:11:51 amYou can mentally filter the search results by package type. In this case I was looking for SOT-89 or similar. Next I look for circuit context (which you provided) to narrow down the candidates.Finally, I try to find a photo of the part:https://www.google.com/search?q=KIA431AF&tbs=isz%3Am%2Citp%3Aphoto&tbm=ischhttps://www.aliexpress.com/wholesale?catId=400103&initiative_id=&SearchText=KIA431AF

author: 2X
author_rank: Frequent Contributor
timestamp: August 22, 2023, 07:53:18 pm
content: Quote from: fzabkar on August 21, 2023, 05:08:54 pmMany thanks for your help. I made a schematic about how the two components "Marking Code 3B 514" interconnected on the PCB with the other components. According to the connections I believe you are totally right that the "Marking Code 3B 514" is a voltage reference. Also, I measured all the pins of the component between them with a multimeter in diode mode.

author: fzabkar
author_rank: Super Contributor
timestamp: August 22, 2023, 08:47:40 pm
content: Quote from: 2X on August 22, 2023, 07:53:18 pmTo be fair, @amyk found your IC. I just added my links to help you in your future searches.

author: 2X
author_rank: Frequent Contributor
timestamp: August 22, 2023, 09:45:30 pm
content: Quote from: amyk on August 21, 2023, 01:52:49 amThanks a lot for the help and your time.