Surface mount board repair?

[drventure]

Anyone know anyplace that does that sort of thing?

I've got a panasonic ae-900u projector. it got a case of vertical red lines about a week ago. Turns out, it's a pretty common prob with these things.

There are 3 surface mount LCD driver chips (all the same from what I can tell) that control each of the RGB lcd panels. 2 of the chips are mounted to a single heat sink, so It's common for them to get hot, overheat and desolder themselves

That's exactly what Happened to mine. I poked around with it a bit and got the pins resoldered, and believe it or not, the thing started working again.

But now, It works perfectly fine for about 3 minutes, then the screen completely scrambles. I'm guessing the driver chip got hot enough to mess it up internally, and now, once it warms up, the chip gets screwed until it can cool back down.

I found the exact same driver chips online, but I have no idea how I'd actually desolder the old chips and install the new ones.

Anyone know anybody or any company that does that kind of repair work (I'm in the Dallas, TX area, local would be good, but anywhere would be ok).

Thing is, a whole new main board will cost me ~600$, which is about what I paid for the projector in the first place. So any repair that would end up close to that, wouldn't be worth it.

So, repair may not be in the cards anyway, but, it's worth exploring...

I was just totally stoked when, after using binoculars backwards to zoom in on those pins (because they're +unbelievably small+ little traces) and a little soldering and xacto knife wielding, I was actually able to get it to work properly again in the first place (even if only for a few minutes!)

[northerngames]

possible to post some high res picks of the troubled area up close and what needs to be swapped out?

I may be able to help but need to see what's going on exactly.

[drventure]

Thanks for the response!

Here's a shot of 2 of the drivers, there's 3 total.
I highlighted the damaged part in red. Looks like a pin came desoldered. I put a little flux on it, heated it with a torch and that "seemed" to do the trick. No more bars. The thermal grease was cleaned up before I reassembled everything to test, so I don't +think+ that's the problem.

But now it flakes out after just a few minutes.



This is pretty magnified. The actual chips are only about .5inch square. Those pins are friggin +TINY+. I'm sure I could get the chips off, but I have no way to solder news ones on.

I was able to find the service manual online, and find the chips themselves, they're about 44$ each. No idea whether one or both would need replacing, but I'm guessing both.

What do you think? Is it worth bothering with?

[northerngames]

I have done xbox ram upgrade's on my own and they were a pain and these seem to be the exact same skill level.

if the xbox failed it was only like a $25.00 mistake where your 3 chips alone are $120.00+ and also something could happen to the motherboard itself wich is probably another few hundred.

to expensive for me to try and I would not suggest you try it unless your highly skilled in that type of stuff and have the correct tools like the hot air gun.

I would try to see if anyone actually does the xbox ram upgrade's still and if so they may be able to do it fast and reliably and also have the correct tools.

[drventure]

Thanks

Yeah, I've been calling around here locally, but I haven't found anyone that would take it on yet.

I'm about to the point of calling it and start looking for another project. That Casio really +sounds+ good, but I can't find squat about it.

Well, thanks for looking and for the confirmation!

[northerngames]

yeah no problem and I would have liked to take it on but unless I know I can do it with 100% success for sure I won't take something of a high value like that on.

if it were a $50.00 setup with a 50/50 shot or something I would take the risk but I dont want to risk ruining something of value like that unless I know I can fix it for sure.

[northerngames]

are those on the main motherboard or a smaller sister board?

was thinking if it is a smaller board you may be able to get it for less then the 3 chips themselve's.

I have found some tv boards on ebay and amazon that I thought for sure no one would have but sure enough someone was parting the one's I needed at the time so dont toss it out or anything.

[drventure]

No, they're on the main pc board. I've done a bit of looking for used parts, but didn't really turn up anything.

It's a dicey repair, but I'm starting to think....well, if I don't repair it, I can either
1) toss it
2) put it up on ebay as a parts box for 10$
3) rip it apart myself and see if there's any little bits in there worth salvaging for something else.

When you think about it that way, it's not like I have much to loose attempting a repair. If it doesn't work, I'm no worse off (other than maybe out 100$ or so).

I just don't know.

[northerngames]

zooming in on the troubled spot is there damage to the trace on the third pin from the top of the right side where you have it in red?

the pic looks like that trace is beatup a little when zoomed in.

if it is you could attach a wire from that pin and jump it to another ground point like that via hole that the other end of the trace runs into next.

also to the right of the chip on the 2nd fuse down it looks like there is a white spot in the center of the brown center take a look at that close and see if it is melted at all or perhaps take a multimeter and check it or perhaps all 5 on that side.

if the pin is not connected good it could work but cause it to overheat becuase it is making contact but not actually connected like a cold solder joint or a cracked soldered joint.

as an example its kinda like the original's xbox power supply they would work even with the cracked points but some got hot and burned up or caught things on fire becuase the solder joint's got cracked where the plug went into the psu motherboard and people wiggling the cord.

happens on laptops and many other things even the psone console's had the same problem when it come's to the power cord ports.

[drventure]

I didn't notice that, but now that you point it out, I do see it. I'll check that out.

I'll also give that jumper wire idea a try. I'm thinking it might very well be that I still have a joint that's not completely connected.

Thanks!

I'll post what I find out. Working on surface mount stuff like this is completely a first for me  . Regular ol' breadboards? No problem, but this stuff? My eyes are getting too old for this 

[Edgedamage]

Anyone know anyplace that does that sort of thing?

I've got a panasonic ae-900u projector. it got a case of vertical red lines about a week ago. Turns out, it's a pretty common prob with these things.

There are 3 surface mount LCD driver chips (all the same from what I can tell) that control each of the RGB lcd panels. 2 of the chips are mounted to a single heat sink, so It's common for them to get hot, overheat and desolder themselves

That's exactly what Happened to mine. I poked around with it a bit and got the pins resoldered, and believe it or not, the thing started working again.

But now, It works perfectly fine for about 3 minutes, then the screen completely scrambles. I'm guessing the driver chip got hot enough to mess it up internally, and now, once it warms up, the chip gets screwed until it can cool back down.

I found the exact same driver chips online, but I have no idea how I'd actually desolder the old chips and install the new ones.

Anyone know anybody or any company that does that kind of repair work (I'm in the Dallas, TX area, local would be good, but anywhere would be ok).

Thing is, a whole new main board will cost me ~600$, which is about what I paid for the projector in the first place. So any repair that would end up close to that, wouldn't be worth it.

So, repair may not be in the cards anyway, but, it's worth exploring...

I was just totally stoked when, after using binoculars backwards to zoom in on those pins (because they're +unbelievably small+ little traces) and a little soldering and xacto knife wielding, I was actually able to get it to work properly again in the first place (even if only for a few minutes!)

Build your own hot air pencil:
http://www.usbmicro.com/documents/ACC430664DD26DDE5986574AAA62775FDFF29EA1.html

[drventure]

Hmm. I never even knew about such a thing! Looks like that, combined with a good head mounted magnifier might actually let me resolder things properly.

Thanks for that link!

[lilshawn]

also to the right of the chip on the 2nd fuse down it looks like there is a white spot in the center of the brown center take a look at that close and see if it is melted at all or perhaps take a multimeter and check it or perhaps all 5 on that side.

actually what you are looking at is actually capacitors. They are just used to help smooth the signals going in ad out of the chip.

zooming in on the troubled spot is there damage to the trace on the third pin from the top of the right side where you have it in red?

I see that too. maybe a small section  of the trace is gone. could just be a lighting thing, but something to check none the less.

[drventure]

Yeah, I'm going to pull it back down and attempt some more repairs. I ended up picking up another of the exact same model off CL over the weekend so no hurries now. If I can fix it, yeah, I'll have a backup or something to put up on ebay. If not, I guess I'll have some spare parts.

Maybe that'll buy me enough time to let the lampless projector market build up.