How i can solder the ....

[ha]

Hey

Please how i can desolder the flash memory like sst39vf160 and solder

another new in the STB ?

Thanks.

 

[eltonjohn]

memories and other components come in different packages. So your question is too imprecise .. mention the package
Is it BGA .? or TSOP or other ..

 

[ha]

Hey

Ok,the package is TSOP 48.

Thankes.

 

[eltonjohn]

Ok you see now we can give you a hand !
The best way is to use a hot air station .. But i assume that you don't have access to it .Otherwise you wouldn't be asking Now tere is another way .Use very small size Solder braid .. You can buy it almost anywhere !

Depending of what you want to do : Do yu need to reuse the memory later or not?
if the component is to be reused then do this
1)with the solder braid absorb all the solder excess .You should be able to get all leads very clean .. be carefull don't apply yo much heat
2) try to adapt a wide flat solder tip to your iron in order to apply uniformly heat to all leads .
3) work first in on one side . pry the memory with a knife ,just enough to lift it a little bit
4) do the same at the other side .! NEVER RUSH.
do this with a lot of PACIENSE!

Finally if the memory is presumly bad and is going to be repleced . Well with a small rotating grinder or even a fine file or knife CUT ALL THE LEADS .. from the plastic casing side of the component . Once the black plastic component REMOVED .. just with the iron and some solder wick clean the leads that remained attached ..
This is very simple .. ONCE again don't apply TOO MUCH HEAT ..Just the necessary !

Wash and clean with water in both cases .. leave it to dry .

To Solder back is better to use SOLDER paste . the type that needs refrigeration..
Apply a little bit pf paste with a painting BRUSH (the finest brush you can get at drawing artist supply shops ..!) to every lead . And with a fine tip iron just apply heat to every lead INDIVIDUALLY !

wipe out the excess with solder braid .. But DON"T SUCK UP all the solder .. just bearly excert some presure !

Listen this is an art that only with experience you will be good at it
The trick is the amount of heat .. Try to do it in a computer board before you tackle the real thing

Good luck!

 

[samcheetah]

hey eltonjohn that was a very informative post. i have one question for u. what method is used in robotic soldering stations for smaller packages like TSOP. which method is the best. like for example what do the motherboard manufacturers use.

 

[ha]

Hey,eltonjohn

I asked for hot air station and i buy it ,could you explain the soldring

option with some pictures (jpg,bmp)format ?thank you very much.

Thanks

 

[s_a_r_a]

I'm agree with eltonjohn but point 1) is not necessary.
If you have not a wide flat solder tip in your solderer
you can put a good quantity of tin on the pins
of the memory and then with the solderer you should distribute it
on all the pins moving the tip from the first pin to the last one on the same side,and back again. During this operation you should force
the memory with a cutter to lift it a little bit as explained by eltonjohn.
When one side is desoldered you could lift and turn down alternately the memory in order to "break" the pins of the other side. At the end you should remove this pins with the solderer.
For a T-Sop package nothing will happen to the pcb.

Best Regards

 

[jhallows]

See attached file on soldering a TSOP. Contains pictures.