Monolithic Soldering Critique

[jeremyb]

Since others think soldering monolithic's by hand is a better approach (I still like my way better) I decided to give it a try and got a microscope. Arvika says it takes him 15 minutes, it takes me a little longer but I guess that's practice.. Does this look okay? Any suggestions? Ruffing up the via a little with a scalpel helps the solder adhere better. Working w/ the thin wire is still a PITA. Need to figure out a better way to strip the coating and tin the wire. Otherwise it seems to work.

Attachments

[HaQue]

still takes me longer than 15 mins, but I don't rush and usually have other things going on. Looks fine. I have found the single most painful part is getting the solder to stick to the end of the wire. Seems to not want to stick if it has been messed with heating up for too long. I think this boils down to the type of wire.
What is your approach, if not by hand?

Once you have to drill down layers to solder to sub-terrain tracks it adds a whole new level of enjoyment...

[jeremyb]

I have found the single most painful part is getting the solder to stick to the end of the wire. Seems to not want to stick if it has been messed with heating up for too long. I think this boils down to the type of wire.

I may have an easy cheap solution for this, I'll know in a few weeks when the part comes.

What is your approach, if not by hand?

Sockets, there is a 2wk lead time (otherwise it gets crazy pricey) and it cost a little money but once you do the first one your set. Problem is I keep running into monolithic's with problem chips or chips that are screwed up in some "other" way beyond what I see in normal day flash so I loose money on unrecoverable cases

Once you have to drill down layers to solder to sub-terrain tracks it adds a whole new level of enjoyment...

I haven't gotten there yet, mostly because i'm very picky about which monolithic jobs I take on. I wish there was a proper database for pin-outs.

[arvika]

Jeremy, I do not see flux on your photo. It is one of the key. Without flux you will have problem with shorts.
Here you have Ace video: https://www.youtube.com/watch?v=tIU6cxIj1XM
IMHO almost everything is done wrong on this film so just try other way. 3-4 pad/15 minutes. It is huge pads, not small one or traces.
I try find some camera and maybe I will record some tutorial.

[jeremyb]

Looks like they're using sparkle paste, I'm not a huge fan of that stuff, soldering pads that big doesn't require much skill.

Lol, I used flux remover to clean the monolithic for the picture. I find using flux degrades the quality of the PCB making it easier to lift traces off the board (severity differs depending of type of flux). I use small amounts, either the flux inside the core of my solder or applying some to the tip of my wire before soldering it. I don't drench my PCB in it.

I don't generally have issues w/ shorts but if I do flux is the solution. Eg: The picture was after wires were attached and removed, no shorts, very little flux was used..

[jeremyb]

I have found the single most painful part is getting the solder to stick to the end of the wire. Seems to not want to stick if it has been messed with heating up for too long. I think this boils down to the type of wire.

I was playing around with some different ideas, try putting some sparkle paste on the tip of your soldering iron when you attach the wire.

[jeremyb]

I was playing around with some different ideas, try putting some sparkle paste on the tip of your soldering iron when you attach the wire.

Terrible idea, just remembered why I hate sparkle paste :-/

New personal best, 1.7min per pin (20 total). Which includes everything, stripping the wire then soldering it to the monolith and breakout PCB.
All soldering was done to the Vias, no contact with the thin traces or copper fill, no flux (besides in solder core) was used. With more practice I think I can get that number down to ~1.2. Using a stereo microscope really helps, great idea.

I still like sockets but soldering is interesting..

[ddrecovery]

I have just returned from the Ace Labs Flash training class in CT as I am trying to improve my skills in flash recovery. They have changed their technique for mono's now. They coat the board with liquid flux, then add BGA solder balls to the pads. These are then melted with a USB (low temp) solder gun. The mono is then warmed with a hot air gun at low pressure (300 degrees) to help dome the solder balls.

[HaQue]

sounds like a lot of mucking about to me.. I am beginning to think just soldering them normally is the quickest way, if you take into account all the different types. Aces way might not work too well for ones you need to drill down and get at sublayers, though I haven't seen their way, only going by your description. I have found getting solder to stick to the wire the hard part, not tinning, doming the pads in readiness. You also don't want to be applying too much unnecessary heat to the monolith.

but there are many different ways and sit is whatever works for you.

was there any mention of their monolith research jig? I saw it a while ago but it seems to have all mention of it wiped out of existence. anyone have a photo of it?

[ddrecovery]

Yes they did have pictures of the jig. Still in the design stage and is due to be launched next year. I think working on micro sd's with the jig might be as hard as soldering as there is not much space. However if it does work it will reduce the workload for certain jobs. I don't have a picture I'm afraid.

[HaQue]

Thanks alot for the info. Yes I don't think there is going to be a wondertool for monoliths. especially when they start being filled with data filled rainbows

[ddrecovery]

I understand about the subterranean pads (although I have never seen one), but rainbows? ?

[jeremyb]

I'm pretty sure I've seen jigs for testing silicon IC's that would work for monolithics but I remember them being expensive.
Solder balls on large pads isn't much of a challenge, try soldering a 0.05mm trace. IMHO they're all terrible methods.

[HaQue]

No easy way to get in contact with the owner of the pic, so I will post only a portion, and hope he is ok with it... but this is the sort of fun you can look forward to. try resting BGA balls on these.. yes it really puts your balls on the line....

subterrainian_nightmare.png (89.92 KiB) Viewed 12617 times

[jeremyb]

Looks easy except I don't know where to dig, guess that's what the X-ray is for. I still don't know what I need to look for in one :-/

EDIT:
Trace width looks like it's 0.07mm.. I have wire that's thinner.
Bottom traces look smashed by pressure so I assume they look more like the top.
Fine tip conical soldering iron tip, use aluminum tweezers to hold wire and act as a heat sink so heat from soldering iron doesn't loosen other soldered wires and work your way back..

I'd worry that I might damage the IC because I don't know where the parts are..

Maybe find a better way to rip up the top layer, I haven't found it yet..
I think it's doable, maybe devote a month to it and see what happens.

[ddrecovery]

Being a noob, I'm still confused about the data filled rainbows??

[HaQue]

Being a noob, I'm still confused about the data filled rainbows??

Sorry it was a kind of humorous(?) reference to light being used in data storage as was recently reported on.

http://www.sciencedaily.com/releases/2015/10/151004112856.htm

will drives containing mostly Pr0n glow blue?

[jeremyb]

Similar to the magic smoke that keeps all flash drives working? When customers, friends or other data recovery shops work on flash drives they may let the magic smoke escape preventing the drive from being easily recoverable. To recover the data I must capture the magic smoke and put it back in the flash drive. If I can't capture the smoke the drive is unrecoverable.

[Izualim]

at the very end is a shame that the customer believes is a straight forward job and we shouldn't charge them that much for just recovering an uSD Card...

[HaQue]

just my luck, I get in a uSD with only about 6 vias on the whole PCB.. I need:
1. Money
2. x-ray
3. laser
4. time
5. reality check!