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How to install:
Soldering the FLEX PCB
It may look complicated but it is not.
DO NOT use the hot air method to solder it! Hot air will burn the FLEX PCB because it is too hot, FLEX PCB is too thin and fragile and not suitable for this particular purpose.
You will need for this operation:
1. Basic repair tools, knifes?
2. Sandpaper extra fine grade 600 to 800,
3. 10 minute epoxy - transparent, non conductive,
4. Zoom microscope with magnification 3x to at least 30x,
5. Liquid SMD flux,
6. Soldering station with adjustable temperature,
7. Any fluid to clean PCB after soldering
8. Compressed air in a spray bottle
To find out what are ?10 minute epoxy?, ?zoom microscope?, ?stereo zoom microscope?, ?SMD flux? and others please search for them using ebay or google.
Locate the red marked areas on your mainboard. They are the same for all mainboards. Only point "A" diferent between TA79-TA81 and TA82-TA86 as you can see here.
1. Use sand paper to remove the solder mask. Do it gently. You must not scratch the ground i.e. do not remove the solder mask from the ground plane?s edges which are in the close proximity to the traces of the area we will solder to.
The both areas need to be exposed from soldermask completely as shown below:
2. Presolder the exposed copper traces with a normal soldering iron and soldering wire. Use a big ball of a fresh solder, move the ball over traces and take it off from the traces again. The pretinned traces must look like this. (Same for the other area of exposed traces)
Here is a small video showing the procedure of presoldering:
This video presents a good presoldering practice. At the first moment
the operator bridges 3 exposed traces and then he removes these
shorts gently. As you take a closer look the operator does not use
anything else then a tin wire with the rosin core. He operates the
tin wire in order to have the rosin constantly fresh. This operation
is very safe for the PCB and traces. Try to lower the temperature if
your rosin evaporates too fast. In general don't use too hot tip.
After this operation clean the remaining rosin by a chemical agent of
your choice.
3. Clean the PCB with pcb cleaner and compressed air.
4. Solder the "B" wire. Locate this area and compare with your PSP. The small cap is either horizontal or vertical (latter only seen in TA86 yet). Solder the wire to the one side of the cap as indicated in the following pictures. You can make a short connection to the point next to it as marked in the pictures for better connection quality.
5. Put some epoxy dots on the PCB - here you can see the "B" wire which must be isolated using epoxy. We wil solder this wire to the flex pcb later.
... and put the FLEX PCB on it. Push the FLEX PCB to the bottom but you must not glue both contact ends as they must remain unglued.
6. Now use a big magnification to make the final alignment of both contacts. You have 5 to 10 minutes for this operation until the epoxy glue becomes cured. This step is one of the most important and most sensitive as the allignment must be 100% straight on both trace areas.
Mix two component fast curing transparent epoxy. Put it on the
motherboard as you see on the movie. Be careful not to put any glue on
the contact parts of the flexible PCB. At the beginning try to
position the flex PCB without magnification and then you need to use
a stereo microscope or a very strong magnification glass. Both
methods will work. You have at least 5 minutes to position each end
to the underlining traces on the PCB. Initial alignment without
magnification is important because after this part of the operation
you will only align each contact pole of the flex PCB at a time
moving the whole flex PCB. After some iterations you will align both
PCB contacts. This second operation is not shown on this movie
because the motherboard was taken under the stereo scope. After every
minute the movement of the flex PCB will become harder because of the
curing epoxy. It is very good factor which helps in the whole
alignment process.
If you don't align it at this point the soldering will not be
possible. It must be the PIN-POINT alignment. Play without the epoxy
first.
7. Leave it for additional 20-30minutes to let the epoxy cure completely.
This video was taken after around 30 minutes when the epoxy is solid
and after we made two ground connections. Do it only if you made the
proper flex PCB alignment. Remove the solder mask by a sharp knife or
screwdriver. Solder both GND points as shown here. These two GND
points have very important additional purpose. They mechanically
protect the flex PCB after bending when the programmer is connected
and mounted on the proper place.
8. Expose the ground copper on the motherboard and solder both ground points of the FLEX PCB to the motherboard. This operation must be done first prior to the final soldering of the main contacts because both ground joints will prevent any mechanical damages and will keep the FLEX PCB on the right angle with a big strength. It must be done like that for mechanical reasons to prevent a mess up.
9. Inspect the alignment of the FLEX PCB and traces on the motherboard. If OK go to the next point.
10. Put a lot of flux between the FLEX PCB and the board. ?A lot of? means that it must be immersed in the flux. More flux is better.
11. Solder all pins together with a big ball of solder for 3 to 6 seconds. Don?t touch the FLEX PCB by the soldering tip but only by a ball of melted solder. During this process apply a little pressure to the end of the pcb with a cold tool. If you replace QFP packages then you understand how to do it. You can use a ?micro wave? soldering tip.
This is the main soldering procedure. Use a bigger ball of tin rather
more than a smaller because the surface tension works better with a big
ball. The ball of tin must be "wet". This video was taken from the
microscope and a built in ocular camera. At the beginning you can see
somebody's hand with a small bottle of the liquid SMD FLUX. This
moment is not sharp because the magnification is big and the focus
depth is very small but right after this moment you can see the
liquid flux spilling around the motherboard and below the flex PCB.
Solder immediately after this, Do not let it evaporate. The next
operation in the movie is the main soldering technique. It may look
strange but the physics and the surface tension are on our side. The big
ball of tin will not allow to bridge even the closest and the
smallest traces. There is only one condition - you must have a lot of
flux and you must help the process by a rosin core inside of the tin wire.
Use only Sn/Pb tin wire. The process is similar to the pre soldering.
Don't touch the flex PCB with the tip, apply small pressure from the
top as you see using a soldering wire in this example. Don't press it
in one place because the rosin will glue the tin wire to the flex
PCB. The idea of this operation is based on the fact that you push the
heat from the front, using a big and "wet" ball of tin and the
"surface tension" helps you in this process. Don't use too hot
soldering iron because you will burn your traces and the flex PCB. If
you fail at the first attempt you can do the procedure again. Clean
the area first, put some flux and solder again. If you keep the
temperature quite low and if you don't scratch the surfaces then you
can repeat the operation even 3-4 times until you get the proper NAND
silicon ID from the software. Clean the area after the process.
Remember: not too hot, a lot of flux, Sn/Pb tin wire with rosin.
12. Clean the area again using pcb cleaner and compressed air.
This is after the main soldering operation. The PCB was cleaned. This
video presents the soldering point from some different angles with a
moving light for better visibility. This video was taken by the
microscope. If you can't read the proper NAND silicon ID then you
need to inspect the soldering and you need to apply the soldering
procedure again. Simply use more flux and solder again to make
missing connections. Black areas between soldered traces and below
the joint point, below the flex PCP is the remaining flux or cleaning
fluid. It will evaporate within an hour but it will not interfere. It
does not conduct electricity and will not harm the circuit. Ignore
it.
13. Now it is time to solder the wires "A", "B" and "C". We already had to solder wire "B" to the mainboard in an earlier step.
14.a For TA79 - TA81 solder wire "A" to the left leg of the MH5. You can make a short connection to the left side of the component below as indicated in this picture for better connection quality.
14b. For TA82 - TA86 solder point "A" to the lower side of the small SMD capacitor. You can make a short connection to the point besides as indicated in this picture for better connection quality.
15. Solder wire "C" to the pin of the power switch as shown here
16. Plug the flat ribbon connector into the socket of the chip using the following direction.
This is a view from the backside
17. Apply a little bit of glue or double sided adhesive onto the Actel IC and bend the chip over like this:
18. Now we see the 4 USB pins of the chip that need to be soldered to the PSP's USB Port. Connect them as indicated here:
19. To be able to make use of the very own USB Port of the PSP we need to prepare a custom USB Cable. The only way we could get this fabulous feature working was by using a free connection of the PSP's USB Port.
Get yourself any mini USB Cable and cut the end containing the mini USB jack. Buy a new mini USB jack from your local electronics store. (Must be MINI-B). Solder the wires of the USB cable to the mini USB jack as follows:
red = 1
white = 2
green = 4
black = 5
After the final soldering you must test if all the previous
operations were successful before you assemble the PSP back to the
normal state. You must make a simple test if it is working or not.
To test it you need he following:
1. PSP motherboard with the DEVOLUTION-PROGRAMMER
2. Power switch connected to the PSP?s motherboard
3. PSP power supply socket inserted
4. PSP power supply
5. Self rebuilt USB cable.
This is the minimum you need to test all electrical connections.
Every Programmer is sold with the 5 pin mini B USB plug. Get a normal
USB cable from the shop, cut the mini B plug from this cable and
replace it with our plug with the only one difference. All USB
signals in the normal cable are connected to pins 1,2,3,5 but you
need to connect them to 1,2,4,5. It means that you need to re-solder
only one cable from pin 3 to pin 4 and no other changes are made. If
you are able open your retail cable you can only re-solder pin 3 to
pin 4. If your cable is strongly melted use our plug and solder all
wires.
Use the following procedure:
1. Connect the self rebuilt USB cable and do NOT connect anything
else
2. Run the programming software and wait for the communication
3. Check if the WiFi switch on the PSP is in the ?up? position
4. The RED LED on the programmer should also go ON after some seconds
5. Connect the power cable and press the power switch to see the
green power LED
6. Then press the ?Read NAND Silicon ID? button on the main window.
Step 6 should return:
0xEC35A5BD for TA082/086
0xEC75A5BD for TA079/081
If you get another value then your soldering is bad!
For example if you receive 0x00000000 or 0xFFFFFFFF then it can be a
bad soldering and/or power supply problem from the side of the PSP
motherboard. Look at flex cable and all around it.
If the value is still different then expected (not zero and not FF)
then your soldering is bad but all other factors are ok. Try to
re-solder a flex cable only.
If you get the proper silicon signature (ID) then you can be fully
sure that you have done it right.
If you mess up the edge contact of the flex PCB then you can replace
the flex or shorten the contact using a microscope. You can simply
shorten them by half or so. You can cut 0.1 to 0.3mm using a surgical
knife and good magnification to cut the melted edge and then solder
again..
Remember!
Always use a lot of SMD FLUX, look for short circuits and don?t kill
the motherboard with the sand paper.
Before assembling the PSP you should either cut a hole into the metal shielding or just leave it away as it is not required in any way.
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