First things first a DISCLAMER if you decide to follow my footsteps: I or GPSUNDERGROUND forum is in no way reliable if you break/brick/destroy your device!
So I got fed up that my TomTom XXL 530S had only 2GB of memory and I couldn't fit the whole map of Europe and/or USA, Canada & Mexico! So I decided to desolder the chip and replace it with a bigger one.
The original chip was Samsung moviNAND KMAKG0000M-B998. With a little digging it turns out its a standard eMMC flash memory. A quick search on jedec.org and I downloaded all past and current releases of the standard. I just had to make sure that whatever I got was going to be compatible.
After some research I bought Samsung KLM8G2FEJA-A002 for 9$ + free shipping.
When it arrived. I got ready to work.
Tools I (thought I) needed.
1) Soldering station. More specifically the air soldering gun.
2) A pair of flush cutting pliers
4) Screwdrivers and reverse pliers.
5) Different kinds of flux and soldering wik.
6) Flux cleaner.
7) The TomTom and replacement chip.
Disassembly of the TomTom is easy, just unscrew the 2 tiny Torx skrews and ply open the screen.
After that remove the 3 phillips screws holding the motherboard...
...just a photo of the replacement chip side by side:
...and then the hardest part starts. Desoldering the memory chip! I put a lot of flux paste around the chip and heated the soldering gun to around 270 degrees.
BE VERY CAREFUL AND DONT RUSH IT!!!!
Not like me, because I ruined the PCB... I lift off a few of the DATA traces and the PCB was unusable. I should have waited a little longer and/or used a higher temperature.
So that was disappointing... I went and bought a TomTom XXL Classic edition for ~25 Euros from a local second hand shop. And I succeeded in replacing it's chip!
Woohooo now I have an 8GB TomTom XXL!
This is the available space after loading the whole Europe map . It has plenty of space to spare for US/Canada maps, maybe even some maps in Asia! Attachment 12263
And here is the final result:
1) 1 working 8GB Tomtom XXL Classic Edition.
2) 2 eMMC 2GB flash chips.
3) Unusable PCB
4) Spare case & screen for a TomTom XXL 530S.
Ok so I was asked for a Step-by-Step tutorial. Here it comes.
1) Remove the info sticker at the bottom of the TomTom.
2) Unscrew the 2 torx skrews as shown on the below photo:
3) You can use a flat-head screwdriver to pry open the snaps that hold the Display from the bottom case.
4) Be careful the display is still connected! So don't lift the display from the TomTom logo's side, but from the other side. Show on the next photo:
5) While holding the display on one side, release the display ribbon cable, by moving the white halve of of the connector! As shown here:
6) Now that we have the display off, set it aside somewhere safe. And proceed with removing the following 3 or 4 skews as in the next picture:
And the tutorial will continue in the next post, since I can't attach more than 5 pics in a post .
7) Lift up the motherboard from the USB side, and disconnect the battery and speaker as shown here:
8) Now that we have the motherboard released from the bottom case, apply plenty of flux (paste) around the flash chip that we are replacing:
The next few steps are the HARDEST! So read them carefully, watch youtube videos, etc. on the subject of (de)solderign BGA chips. Educate yourself
9) Desolder the chip! A nice video on how to de(solder) a BGA: https://www.youtube.com/watch?v=L8EWqWj2srg
NOTE: This is the step where I messed up bad, and ruined my TomTom XXL 530S and had to buy another TomTom XXL. I lift up the pads which were important! A nice idea, if you don't have experience desoldering BGA parts, is to use old PCBs and just practice desoldering!
10) Clean the PCB pads from leftover solder, with flux and solder wick:
10.5) I cleaned the flux with a PCB flux cleaner and applied a new fresh coat of flux paste where the replacement chip will stay.
11) Solder the replacement chip! Don't forget to match the little arrow with the dimple on the chip! I used reverse pliers to hold down the chip like this diagonally:
Note: The eMMC flash standard has a few footprints for what the chip can be. It's lucky that the silkscreen on the TomTom PCB has all of them. So no matter what replacement chips you use it will match one of them. And by match I mean to the .1 of the millimeter.
12) Assemble the TomTom by following steps 7 to 2 backwards.
13) If everything went well, when connecting your TomTom to a PC, it should promt you that it needs to be formatted! Format as FAT32, install a Navcore, maps, etc.