New guy question - How to identify smd components - Page 1
Forum section: electronics / repair

author: nitzane
author_rank: Newbie
timestamp: December 28, 2019, 07:34:48 pm
content: Hey guys,Im trying to fix a ps2 that wont turn on. the poer supply works fine (outputs the specified voltage), and the on/off button works on continuity.i went further down what lookes like the power rail (there are no schematics for this specific model) and i stumbled upon some corroded looking components.i want to get replacements but i couldnt make out types/specs of individual components.Hoping you guys can help, ive added some pictures.Nitzan

author: WyverntekGameRepairs
author_rank: Regular Contributor
timestamp: December 29, 2019, 02:20:09 am
content: Not much you can do for the SMD non-polarised capacitors and unmarked inductors at the moment... For now, I recommend using 99% isopropyl (rubbing) alcohol to scrub down and clean the corroded areas of the board. Then, look at all of the parts that do have values and numbers written on them, and replace those. If the corrosion hasn’t completely destroyed the values of the np smd caps, you can try and measure the capacitances of them and getting replacements after you confirm the values. But be very careful, if you get an incorrect value smd cap, it could affect the circuit performance very negatively - Worst case scenario, it’ll go *boom*Until you are certain of what you are doing, I recommend sticking to replacing the components that have markings. You can get an app on your device that can help you identify component values and look up data sheets. I have EE Helper installed on my iPhone and it is a toolbox of tools for data sheets, calculations and value decoding and whatnot. There are many apps that can do that too. I hope this helps!Good luck, and don’t blow anything up!-Sterling Ordes

author: nitzane
author_rank: Newbie
timestamp: December 29, 2019, 07:56:28 am
content: Thank you, ill try using alchol to clean stuff. in regards to the caps- im not too optimistic on getting numbers...the board is a scph-90004. by your avatar im gonna go on a limb - do you have its schematics by any chance?

author: WyverntekGameRepairs
author_rank: Regular Contributor
timestamp: December 29, 2019, 05:48:40 pm
content: Quote from: nitzane on December 29, 2019, 07:56:28 amRemember, use the highest percentage IPA you can find. Lower percentages are diluted with more water, and present more risk for water damage. It also leaves gross sticky stains. Get 99% or 98% wherever possible.I repair game consoles and peripherals as a hobby and soon to be business. This revision of the PS2, I do not currently have schematics for. However, I’ll take a look around and try to find one. I’m pretty sure I can eventually get my claws on one if I turn over enough rocks.Anyway, glad I could be of service to you. Good luck!

author: Gyro
author_rank: Super Contributor
timestamp: December 29, 2019, 07:55:29 pm
content: Forget about the capacitors for now, that board has been powered for a good while with some ionic liquid on it (cat pee is common under TVs). The copper in many of the vias (and maybe some top side tracks in the corner) is corroded out.Clean locally, first with a mixture of distilled water and IPA, several times (IPA alone won't dissolve the salts) and then finally neat IPA to remove the moisture.You will need to repair each of the rotted via holes by feeding bare tinned copper wire through them (hopefully standard 22 AWG), scraping away solder resist from the tracks until you reach clean copper, and then solder on both sides.If the corrosion hasn't got under the BGA packages, you may stand a chance. That square IC package (35240?) next to the regulator looks bad though, clean around it carefully and make sure none of the pins have corroded away.P.S. Have you looked at the underside of the board?

author: TiN
author_rank: Super Contributor
timestamp: December 29, 2019, 09:27:46 pm
content: I'd say this board is junk, based on photos of extreme damage from liquids. Being multilayer PCB chances that it will work even after replacement of all components are near zero.

author: nitzane
author_rank: Newbie
timestamp: December 30, 2019, 05:36:40 pm
content: Thank you guys,i guess im going to keep this one for spare parts from where liquid damage didnt affect the board.