Discussion:
OT-SD card repair?
Add Reply
rwwink
2017-06-10 11:04:24 UTC
Reply
Permalink
Raw Message
Way OT and most likely the wrong grougp but
I have a 4 MB SD card that has physcially bit the dust. The termain
end has split and broken with a number of the terminals sunk lower
that the others. Would anyone have an idea how, or if, it's possib;e
to bring the card back so I can backup the file that are on the card?
Running W7 x64
R. Wink

---
This email has been checked for viruses by AVG.
http://www.avg.com
Paul
2017-06-10 13:21:43 UTC
Reply
Permalink
Raw Message
Post by rwwink
Way OT and most likely the wrong grougp but
I have a 4 MB SD card that has physcially bit the dust. The termain
end has split and broken with a number of the terminals sunk lower
that the others. Would anyone have an idea how, or if, it's possib;e
to bring the card back so I can backup the file that are on the card?
Running W7 x64
R. Wink
There are data recovery companies who recover data from
Flash media. And they charge a lot, considering no cleanroom
and Class 10 airflow is needed, to work on flash. It should
not require $500 of labor to recover the data.

If I was working on it:

1) Buy a USB to SD reader, one where you know you can
separate the casing on the thing, and gain access
to the socket. This is so you could (attempt) to join
the reader contacts to the SD contacts, without
relying on the normal "spring" action.

2) Some low temperature solder, in case the socket
idea isn't working out. Something like ChipQuik.

https://en.wikipedia.org/wiki/Solder

Bi Pb Sn In 58C "Cerrolow 136"
Also the ChipQuik desoldering alloy.

ChipQuik is normally used to "poison" a solder connection,
dropping the melting point to a level where you can slide
dental floss between a chip and the substrate, while the
chip is only moderately warm. It's an aid in situations where
you would otherwise not be able to separate all the contact
points at once. In this case, you'd be using it, to attempt
to make a temporary connection to the contacts, without
upsetting any higher temperature materials inside.

You would preferably not want to use solder if at all possible.
I don't even know if anyone carries ChipQuik any more. The trick
is to get one of their small samplers, at a reasonable price. Not
a huge kit with a pound of the stuff in it. Even a small sample
of the stuff is expensive.

*******

The Wikipedia article shows some examples.

https://en.wikipedia.org/wiki/Secure_Digital

You can see why you wouldn't want to get the PCB too hot, as
there are surface mount components in there.

Loading Image...

And this more modern one, the controller chip is a "glob-top".
There is a bare silicon die, underneath the black plastic bump.
It's wire bonded (or gold bumped) to the substrate, then the
black plastic is applied on top of it. Glob top was first applied
to digital clock designs, many years ago.

Loading Image...

HTH,
Paul
J. P. Gilliver (John)
2017-06-10 14:14:08 UTC
Reply
Permalink
Raw Message
Post by Paul
Post by rwwink
Way OT and most likely the wrong grougp but
I have a 4 MB SD card that has physcially bit the dust. The termain
end has split and broken with a number of the terminals sunk lower
that the others. Would anyone have an idea how, or if, it's possib;e
to bring the card back so I can backup the file that are on the card?
Running W7 x64
R. Wink
[]
Post by Paul
1) Buy a USB to SD reader, one where you know you can
separate the casing on the thing, and gain access
to the socket. This is so you could (attempt) to join
the reader contacts to the SD contacts, without
relying on the normal "spring" action.
Seconded. Probably get the reader from a poundshop (or the US
equivalent) - mainly because it's for this one-off activity so you don't
want to spend much, but also, the ones they sell are more likely to be
flimsily made!
[]
Post by Paul
You would preferably not want to use solder if at all possible.
[]
Post by Paul
You can see why you wouldn't want to get the PCB too hot, as
there are surface mount components in there.
[]
Post by Paul
And this more modern one, the controller chip is a "glob-top".
There is a bare silicon die, underneath the black plastic bump.
It's wire bonded (or gold bumped) to the substrate, then the
black plastic is applied on top of it. Glob top was first applied
[]
Although since these wire bonds are spot-welds rather than solder, they
can be surprisingly robust!

You could also try building up the contacts with (maybe several folds
of) tinfoil or similar. (Ideally get a scalpel for cutting it, unless
you're better than I am with scissors!) Use a long strip, so you can
fold it back round the other side of the card, so it doesn't come loose
inside the reader. Sort of
|\
CZC| where C is the card and contact surrounds, and - / \ Z
CCCCCCCCCCCCCC| are the foil.
--------------/
(If the depressed contacts are adjacent, maybe some double-sided tape on
the back of the card to keep the strips straight and not touching each
other.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)***@T+H+Sh0!:`)DNAf

"Bother," said Pooh, as he tasted the bacon in his sandwich.
Loading...