SMD rework services in NH USA for reverse engineering proj - Page 1
Forum section: electronics / beginners

author: telengard
author_rank: Contributor
timestamp: October 02, 2019, 05:30:42 pm
content: I've been working on a project for a while, reversing an old Roland sampler with the plan to make changes/fixes to the firmware. This is my projecthttps://www.mv-nation.com/index.php?topic=227.0I've made a lot of progress, but reading the flash chip on board has been a long ongoing process with little results. I'm using a FlashCat with an adapter and chip clip specifically for the flash chip on board ( Toshiba TC58FVM5B2ATG65BAH TSOP48 .5mm). I've tried a ton of things (powering externally, holding CPU in reset, etc), but no luck. So, I'm thinking if I could get a socket on there, I could read/write flash much easier out of circuit. The whole reason I need this is for recovery in the event I upload some bad code, etc. Don't want to brick the machine.I currently don't have the means or skills to do any kind of SMD work on this level, and am wondering if services exist for the hobbyist where they could remove the flash chip and install a TSOP48 .5mm socket on board, like this:https://www.aliexpress.com/item/32754762525.html?spm=a2g0s.9042311.0.0.60814c4dBXwXc4I have reached out to a few local companies and haven't heard back. My guess is they only deal w/ established companies.I live in New Hampshire, USA... any pointers/ideas would be greatly appreciated!

author: JustMeHere
author_rank: Frequent Contributor
timestamp: October 02, 2019, 10:51:51 pm
content: Don't be afraid of SMD. Get yourself a hot air rework station, an old circuit board, practice, and dive in.

author: GerryR
author_rank: Frequent Contributor
timestamp: October 03, 2019, 01:38:54 am
content: I've been away from NH for quite a few years, but used a small electronics assembly house in Laconia. I don't remember the Company name but the owner's last name was Navoy, (Corey and Pete). I am sure they could do what you want, if they are still in business. Try the phone book. Great people to deal with.

author: sokoloff
author_rank: Super Contributor
timestamp: October 03, 2019, 02:00:08 am
content: Note that some of the TSOP48 sockets don't have the same footprint as the TSOP48 chip itself, so be sure to check that. (If you already have the socket in hand, presumably you've figured this out.)I agree this isn't an overly difficult repair task with hot air.I can do it for you in Cambridge, MA or Waltham, MA. (No fee and no guarantee, but this one isn't rocket science so chances of success are very high.)If you're in Salem or Nashua area, that's probably workable; less so if you're up in Lebanon...I'm with JustMeHere though; this is a fine time to dive in, tear apart a few obsolete boards as practice, and then dive into the space MV.

author: telengard
author_rank: Contributor
timestamp: October 04, 2019, 12:32:36 am
content: Thanks everyone for the ideas, and yeah I do plan to get a hot air rework station in the future and learn to use it, but I'm knee deep in this project and the chip is pretty fine pitch. I do some SMD work for mods on my synths, but this is a few levels of difficulty higher for me. I used to do ECO work on this stuff a LONG time ago, but my eyes aren't what they used to be.@sokoloff - I live on the Mass border (Hudson, NH), and the company I work for is in Waltham and I go up there from time to time, really appreciate your offer.I haven't purchased the socket just yet since I wasn't sure I could find a way to get it installed. Not sure what to look for so any pointers would be helpful. I assume it is a pitch/spacing thing? The ali express part doesn't really have a lot to go on other than TSOP48 and .5mm. I've attached a pic of the dimensions of the chip I'm trying to read.

author: Rick Law
author_rank: Super Contributor
timestamp: October 04, 2019, 02:30:54 am
content: I am but a hobbyist with limited experience, so I don't want to seem presumptuous. But, I must say, practice is the key. I did my practice using some dated cell phone - Gen1 Gen2 working phones no one supports anymore.Since those old phones are worthless, I can practice with disregard to destruction. I look for the tiny smd IC's, desoldering it and then solder the darn thing back on. In desoldering, I don't care because presumably I am removing something not working. In soldering, I put a time limit - my hot iron cannot be in contact with the smd-legs exceeding one second. I've redone the same chip so many times and at times so poorly that I melt legs completely off the SMD, but I got better. After a 2 to 4 weeks of may be 2-4 hours per week of practicing (and with a lot of leg-less SMDs). I managed to resolder on IC's within my 1 second per-touch limit most of the time. I did a couple of real repair work on tiny (0.5mm pitch) SMD. My first two attempt were both successful - very lucky.I am no expert, but having done that, now tiny SMD's are not so intimidating to me anymore. I repair/rework SMDs rather freely these days. I still kill chips now and again, but more often than not, I get it soldered/desoldered properly.Those tiny things, I believe, is a matter of overcoming the intimidation factor. Go to it - and after a while, it won't be so intimidating anymore.

author: telengard
author_rank: Contributor
timestamp: October 04, 2019, 02:50:58 am
content: What you mentioned is exactly why I would like someone with experience to do this particular chip. I had read that excessive heat on the flash could wipe it's contents (I'm not sure if that is true, just what I read). But I *really* want to keep the contents of flash intact so I can get a dump of it with the Flashcat. With my luck I'd ruin it.Definitely a good idea to just work on stuff that is worthless, and that's the approach I'll take when I'm ready to start learning.

author: telengard
author_rank: Contributor
timestamp: October 04, 2019, 02:53:57 am
content: Also, I found this socket listing, which seems very similar but there are more specs mentioned.http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=361490149538&category=36327&pm=1&ds=0&t=1553243344000&ver=0

author: KL27x
author_rank: Super Contributor
timestamp: October 04, 2019, 07:57:51 pm
content: QuoteIf it's indispensible/irreplaceable and it's on a multilayer board, I would consider possibility of cutting the communication traces on the board and attaching fly wires to it to read the contents. Then attempt to remove it and fix the traces. That's if those traces are accessible.This is also something for which I'd consider buying/using Chipquick bismuth low melting temp solder. Flood the pins with it before attempting to remove it. On a 2 sided board, you could often remove a TSOP with just an iron, and at pretty close to normal soldering temps. But it will dramatically reduce temp to remove it with hot air, as well.If it's a two layer board, it should be easy for anyone with a hot air gun and a couple days of experience to remove it without damage. On a multilayer, it should still be not too bad. A memory chip doesn't dissipate much heat, so it doesn't need a lot of thermal coupling to the board, but there can be quirks of design/location that cause some problem requiring preheater or oven or whatnot.

author: Syn-Fi
author_rank: Newbie
timestamp: March 24, 2023, 04:46:23 pm
content: CN1 the 50pin socket nearby isn't that wired to the flash rom chip in question. you could jumper what you need to pull the data off the firmware. Also isn't there a roland update file for the MV8800 which you could run through a dissembler ?

author: TC
author_rank: Contributor
timestamp: March 25, 2023, 03:38:35 pm
content: Have you considered removing the Flash, socketing it for use with your Flash tools (reading it) externally, and then placing it back on the board? That minimizes the risk the to original PCB. You could easily make a small PCB that has the socket and whatever connectors you need for your Flash tool for cheap money. If you can't afford to risk the damage to the original equipment I'd give this approach some thought.