Convert MCA into MCA-Plus (Video-In retrofit tutorial)

[Go4IT]

Hey guys! This is what you waited for so long. As i currently doing a small series of retrofitting standard MCA satnavs into MCA-Plus with video input for reverse parking camera, or whatever videosource you like, i'll explain step by step how to do it. I will add photos, hints and of course BOM (bill-of-material). I will add this to this post, also i lock this post as it should be a tutorial to follow, so please ask question in this related topic.

Beware that this retrofit involes about 100 extreme small parts (SMD 0402 is only 1 x 0,5 mm, or 0,04 x 0,02 inch in size!). You should have done this bevore with some experience to get it done. Also you need at least some minimal equipment like:
- Hot air solder station
- Soldering iron with a small tip (1 mm)
- Unsoldering wire (1 mm and 3 mm)
- SMD solder paste
- Flux paste
- PCB holder bracket
- Magnifying lamp (2,5 - 3,0 times)
- Microscope (35 times)
- Cleaning tissues, brushes and alcohol

Let's start with the hard part, applying all missing parts onto the graphics board of the MCA to make it an MCA-Plus. This is what it's all about. Here are some pictures of a MCA and a MCA-Plus board (you find the difference):

video-in_unbestueckt_bu.jpg

video-in_bestueckt_bu.jpg

video-in_unbestueckt_bo.jpg

video-in_bestueckt_bo.jpg

[Go4IT]

First, remove 2 resistor arrays and 2 resistors from the bottom of board (red crossed):

video-in_bu_remove_parts.jpg

[Go4IT]

Put Capton-tape around parts that should be protected by the heat of the hot-air gun:

IMG_4228.JPG

[Go4IT]

Next, we need to remove all the tin from the pads. For this, heat up the area with hot-air for a while, then apply flux paste to it (will do much better if the pads are warm). Now use a strong iron with a big tip (5mm flat, V-form) and some desoldering wire to remove all the tin. I use Techspray NO-CLEAN #3, because for me it's best and i tried a lot different brands and types, but feel free to use your favorite one.

After this, clean everything with alcohol tissues and it should look like this:

video-in_bu_tin_removed.jpg

video-in_bo_tin_removed.jpg

[Go4IT]

Now let's start soldering the first parts!

For this i use SMD soldering paste and a very small Luer-Lock injection needle (yellow) to apply little ammounts of paste onto the pads. Before that i heat up the area with hot air, which makes it easier to put the paste on. Then put the parts onto the pads, one by one, gently with no pressure, using a magnifying lamp.

After you placed them all, apply hot air until the paste melts to tin. This can take serveral minutes, depending on the ground-layer size around the part. Use very low blow-pressure to not blow the parts away! Wait until the paste is completly melt into tin. When the paste melts to tin, the flux inside the paste will also "magically" pull the parts into their exakt orientation. Always beware of the small resistor array pitch. It's easy to make an unwanted solder bridge here. As always, check afterwards using a microscope for shorts und bad solder.

I will start placing parts on one side and go clockwise until all set. I use small areas each time as you can only apply heat onto a small spot at one time. Also i start with the smallest parts and continue with the bigger ones.

The very first parts we solder here are:
2x 100 nF / 25 V, size 0402
2x 1 nF / 25 V, size 0402
1x 33 Ohm resistor array, size 0402

After that, it should look like this:

video-in_bo_parts1.jpg

[Go4IT]

We continue on the right hand side down with:
4x 33 Ohm resistor (0402)
2x 100 nF cap (0402)
1x 1 nF cap (0402)
1x 470 Ohm resistor (0402)
1x 33 Ohm resistor array (0402)

video-in_bo_parts2a.jpg

After those small parts, we place the bigger ones:
1x 10 µF (1206)
1x BLM21AG (0805)
1x 470 nF (0805)

video-in_bo_parts2b.jpg

[Go4IT]

Continue at the lower side (6 o'clock position) with:

7x 100 nF (0402)
1x 1 nF (0402)
2x 100 pF (0402)

video-in_bo_parts3a.jpg

Again, solder the bigger parts last (also i do this with soldering iron instead of hot air):

5x 10 µF (1206)

video-in_bo_parts3b.jpg

[Go4IT]

Now we close the first round by applying these parts:

2x 100 nF (0402)
1x 10 nF (0402)
2x 1 nF (0402)
2x 15 pF (0402)
1x 1.8 kOhm (0402)
1x 33 kOhm (0402)

video-in_bo_parts4a.jpg

Now solder the bigger parts by hand:

2x 10 µF (1206)
1x 68 nF (1206)
1x 15 nF (0805)
2x BLM21AG (0805)
1x ABM8G-28.636MHZ (orientation turned, as on the photo!)

video-in_bo_parts4b.jpg

[Go4IT]

And now as the very last part of the boards upper side, and also the heart of the whole system, the Video ADC:

1x ADV7181C(W)BSTZ

video-in_bo_parts5.jpg

To solder this kind of chips, i first place them on board, align all pins to the pads, fix position with a tweezer and solder one outer pin (even if you make a tin-bridge here, that does not matter now) and also the one on the opposite, diagonal side. Then apply a bar of Flux on each row and use a small soldering iron tip with a bit of tin and go from pin to pin.

When done, check all pins for shorts using a microscope. Clean everything with alcohol (brush and tissue) and remove the Capton-tape "heat-shield" from the connector on this side.

First side done! Now head to the bottom parts...

[Go4IT]

And now we will continue placing parts on the bottom side of the graphicsboard:

1x 0 Ohm (0402)
1x 33 Ohm (0402)
3x 10 kOhm (0402)
1x 22 kOhm (0402)
1x 180 kOhm (0402)
1x 470 kOhm (0402)

1x 1 nF (0402)
2x 100 nF (0402)
2x 1 µF (0402)

1x BLM18AG (0603)
1x BAV99 (SOT23)
1x 74LVC1G14GW (SOT353-5)

video-in_bu_parts6.jpg

This time i solder the integrated circuits with the other parts in one go, because they are somewhat small to solder by hand.