Help identifying capacitor - Page 1
Forum section: electronics / repair

author: Jaxmoto
author_rank: Contributor
timestamp: January 03, 2016, 01:03:18 am
content: Probably simple for someone who works with this stuff daily, but I am having trouble finding it.What I believe is a capacitor, surface mount, marked "15" over "1E39". On a motherboard for a current generation laptop.Somehow it popped and seems to be preventing any power from getting to the battery to charge. I can do the replacement, just need to find the part.Thanks for any assistance.

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 03, 2016, 02:21:46 am
content: Is it still in the circuit (soldered to the board)?It seems more likely that it failed shorted (which caused the overheating) and is preventing the power from getting through. Does it work when you remove the capacitor?

author: Jaxmoto
author_rank: Contributor
timestamp: January 03, 2016, 02:54:46 am
content: I got it off a bit ago, but it mostly just crumbled to bits and just needed to solder off the feet. Everything acts the same with it off, laptop runs fine, shows that it cannot detect the battery. Pads where it was located have the full 19 volts going across.I just can't identify that cap (assuming that is what it is, only 2 connections). It is an Asus, so they have to be floating around out there... but after about 3 solid hours of searching I don't have anything on that specific marking.

author: JSnyder
author_rank: Contributor
timestamp: January 03, 2016, 03:30:36 am
content: My best guess would be Panasonic polymer tantalum, POSCAP, probably the TQC series based on the markings, the "15" at the top refers to the capacitance, "1E" refers to the rated voltage (25v) and the last two digits are a lot code. part no. 25TQC15MV (you'd have to measure the case size to get the right one)http://www.mouser.com/ds/2/315/TQC_OS-262397.pdfhere you can find the series infohttp://eu.industrial.panasonic.com/sites/default/pidseu/files/downloads/files/id_poscap_e.pdfhere (pg. 42) you can find the breakdown of the markings

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 03, 2016, 03:39:53 am
content: Not clear whether "shows that it cannot detect the battery" means that it is working PROPERLY, or if that means it is is broken and UNABLE to detect battery? Can you clarify explicitly?If it still has non-operational functions, that may mean that the blown capacitor is not the only damaged component.

author: helius
author_rank: Super Contributor
timestamp: January 03, 2016, 03:54:21 am
content: I agree with JSnyder, that is some type of solid tantalum. You can usually tell tantalums because they have the (+) side marked, in contradistinction to aluminum electrolytics that mark the (-) side.

author: Jaxmoto
author_rank: Contributor
timestamp: January 03, 2016, 04:31:13 am
content: Quote from: JSnyder on January 03, 2016, 03:30:36 amYep, I think you nailed it, thanks. Crossing that number to another Sanyo data sheet shows it is the correct size and Sanyo uses those markings. Got a few on order from Digikey so I'll see if it works in a few days.Thanks again. You guys rock.Quote from: Richard Crowley on January 03, 2016, 03:39:53 amSorry, should have said both the battery and battery charging are not working properly. I think, because it is a lithium ion battery in this model, that it has just gone totally flat and cannot be detected, but I'm not sure. The bad cap could be causing just the no charging issue, or more issues with the battery. Thanks to JSnyder I know the part and have it on order, so I can go from there.