Question OM6 Trim & output cable

[ultimasnake]

Hey guys/gals (me again!),

Since I've had no luck with my OMGWTF trim on the 4 layer board and I do really want to get further along on my project I started trimming a 6 layer board through the OM6 guide. I've bought 4 wii's now through several markets and they all turned out to be the 6 layer version but since i'm a n00b I think it's better this way (less battery life it is!).

I've got a feeling i'm either not doing something right or maybe i've got a microshort in between layers since I'm reading the incorrect voltages (over the correct lines).

I do know the following:
- Board is C/RVL-CPU-01 A-1 Side-B
- The 1.8v wire is a bit short and runs to close past the processor but for now I think it will do as a test
- I kept the video/audio output on there in the hopes I can keep using them for my mod (if they must be removed for this all to work let me know!)
- I think the short is either around the 1.8v, 3.3v or 1.0v
- No video signal (obviously, else it would work)
- I forgot to measure voltages before cutting it
- the board was working before cut AND was running Portablize mii.
- Sanded the sides with grid 400, might have to keep doing this but on my 4 layer I went to far in at some point (My guess anyway)
- The regs have been tested before placement

This is the board as it is right now





These are the voltages and the resistance (in ohm) that I measure. Ohm is measured without power.



It's night time here so hope you guys can help me out... Oh all has been measured with my Fluke 77 Series 2 Multimeter (not some dollar store product )

 

[Noah]

Remove the wires coming from the regulator and make sure the regs are outputting the correct voltages without being connected to the Wii. That will let you know if the issue is with the regs or the Wii.

 

[ultimasnake]

Remove the wires coming from the regulator and make sure the regs are outputting the correct voltages without being connected to the Wii. That will let you know if the issue is with the regs or the Wii.

The regs have been tested succesfuly before placement (added it to 'the things I know' list)

 

[Shank]

I haven't worked with 6 layer board trims much, but if I had to guess, I would say it's a problem with your 3.3v line and 1v line.

The onboard linear 1.8v regulator is powered by the 3.3v line, so if you have a problem with the 3.3v line, it will mess with the 1.8v one. The 3.3v line also powers the U10 chip.

The 1v line resistance to ground seems too low, like there is a short.

 

[ShockSlayer]

 

[ultimasnake]

oooh dear! that didn't even caught my eye!... so what do we do, remove, try to fix it?.... it seems to be right in between the red line on the trim instructions so it's a bit unclear to me

 

[ultimasnake]

I haven't worked with 6 layer board trims much, but if I had to guess, I would say it's a problem with your 3.3v line and 1v line.

The onboard linear 1.8v regulator is powered by the 3.3v line, so if you have a problem with the 3.3v line, it will mess with the 1.8v one. The 3.3v line also powers the U10 chip.

The 1v line resistance to ground seems too low, like there is a short.

Would it make sense to state that it needs more sanding to the output part of the board? I did not cut/sand where all the cut was already in the board (you know the indent)

 

[ShockSlayer]

Try to fix it I guess. It probably doesn't do anything important though.

 

[ultimasnake]

Try to fix it I guess. It probably doesn't do anything important though.

I now know why it didn't catch my eye. I was still sanding and sanding and sanding after I took the picture, it already dropped off in the meantime.

I also just made the board flush at the same point towards the video output so I have a straight area to sand on (and not more corners then required that where quite hard to sand). Tomorrow I will get 600 and 800 grit (maybe a bit higher since it might always come in handy) and continue the sanding.

I do seem to get better resistance on the 3.3v line now! (but still retains a 'perfect' 1.003volt)