Serious heat issue with Fuze V2

[nexekho]

Ok, I understand that the Fuze V2 port isn't yet considered even stable but I've been playing around with it and it seems stable enough.  I'm more worried about the blistering heat Rockbox seems to cause the little device to put out; it never even gets warm with the original firmware and fourty seconds of metronome is enough warrant to cause the screen to flicker and die (probably owing to the heat damaging the ribbon cable; when it cools down it comes back) and the battery to empty.  I fully comprehend that it's a freetime project and it's nowhere near complete, but this is a serious potentially device ruining issue that I personally believe could warp/desolder components in minutes and the CPU clock rate needs to come right down before a Fuze blows up.

[Chronon]

Solder requires very high temperatures to melt.  I am pretty confident that the temperature of your player is quite a large margin away from this.  If a cable was damaged, cooling would do nothing to improve its operation.  The phenomenology that you are seeing most surely has another explanation.  LCD not operating correctly probably has to do with some chip overheating. 

It would be much more helpful if you can figure out exactly what conditions cause this behavior to appear. 

Are other Fuze v2 owners seeing anything similar?

[nexekho]

It hasn't actually fixed; after about ten minutes it's started flickering and the brightness appears capped at 40%.  There is another thread where normal Rockbox usage has killed a FuzeV2's LCD.  In my case it appears to be linked to the glowing ring of light; the screen problems only persist when it is on.  Weirdly, it seems perfectly capable of displaying video on full screen brightness unless I do something that lights up the ring.

[saratoga]

I fully comprehend that it's a freetime project and it's nowhere near complete, but this is a serious potentially device ruining issue that I personally believe could warp/desolder components in minutes and the CPU clock rate needs to come right down before a Fuze blows up.

With the clock maxed out, the CPU only puts out ~150mW, which is not enough to heat the inside more then a degree or so.  The only thing in the Fuze capable of generating that kind of heat is the lithium ion battery, and only if it fails.  I strongly recommend you replace your fuze immediately.  Serious battery failure is a fire hazard. 

[nexekho]

The battery in the Fuze is up top (I know, I've taken one apart before to try and save it from water death, sadly I failed) and this heat is coming from the very bottom left corner whenever the blue ring is on.  The PCB shows that there is a big blocklike component of some description which looks like some kind of power amp.  Given its close proximity to the USB socket I'd say that's what RB has possibly blown up.

[saratoga]

The battery in the Fuze is up top (I know, I've taken one apart before to try and save it from water death, sadly I failed) and this heat is coming from the very bottom left corner whenever the blue ring is on.  The PCB shows that there is a big blocklike component of some description which looks like some kind of power amp.  Given its close proximity to the USB socket I'd say that's what RB has possibly blown up.

Its some analog component so I doubt this is a rockbox problem.  Since we don't really use it I'm not sure what it does.  Maybe a voltage regulator for the battery or the LED lights.  Either way, my point stands, something has failed completely and you absolutely should not turn the player back on.  Replace it. 

[funman]

Perhaps the button LEDs are not designed to be powered on for 10 minutes as the OF never does that unless you scroll for 10 minutes.

1 minute with LCD on and LEDs on doesn't cause any heating on my fuzev2

[nexekho]

I'm not entirely convinced.  It isn't covered by warranty because technically it's a screen issue (which pretty much no limited warranty on the planet covers) and the power management system could easily experience undefined behavior if the wrong registers are set, etc.  To you who said you've had one running with no problems, run Doom for fifteen minutes with the screen on full and see how long it lasts.  I've also noticed that the original firmware now says "GOODBYE" when I turn it off; it never used to do this before I installed RB and even after reintroducing the firmware that used to be on the device it still comes up with it.  Weird.

[funman]

I think the OF introduced "GOODBYE" message a long time ago (on Clipv1/Fuzev1 at least, I don't remember if it was ever absent in Fuzev2 releases).

Do I have to actually play doom to cause overheat or can I just run it and leave it for 15 minutes?

[nexekho]

Mine started having problems with metronome but it got rediculously hot with most plugins.  Also make sure your brightness is on full.

[funman]

Does it happen if you reduce brightness?

[bolski]

I have felt it get warm, but no warmer than it's gotten with the normal firmware.

I've played Rockbox for Fuze v2 for about 3 hours straight on a trip this past weekend in my car and no screen flicker or anything.

[funman]

The backlight current (in sink1) can be modified in 32 steps of 1.2mA (0 - 37.2mA)

Perhaps 37.2mA is too much?

I never use full brightness.

[Jennifur]

The backlight current (in sink1) can be modified in 32 steps of 1.2mA (0 - 37.2mA)

Perhaps 37.2mA is too much?

I never use full brightness.

It might be. I don't know the math off hand though.

[saratoga]

37 mA is comparable to the normal current of the player, so thats not going to heat up the device.  Its also not that much current split across 4 LEDs. 

Since the battery was implied to discharge a lot faster then the 5 hours that would take driving the LEDs, I don't think its the issue here.