Re: Dell U2311H, display turns off after some time, requires unplugging to reset

Update: After much prodding with the multimeter, one of the zener diodes in the protection circuit seemed to be dropping less and less voltage over time, and the resistor in series with it was the one being monitored on the protect pin, so eventually there would be >2.5v across the resistor. I replaced the diode and it seems to be working ...so far... Of course that could have just been a symptom (the diode going wonky), time will tell.

Re: Dell U2311H, display turns off after some time, requires unplugging to reset



I did go over all the joints with a loupe, they all look great.

The kicker is, nothing really seems to even get hot, the issue still happens just the same with no load (i.e. the logic board and backlights unplugged). There will be correct 3/5/12v output for a bit, and then the IC just shuts it all down once that protect pin hits 2.5v.

I haven't tried the hair-dryer, but I'm pretty sure the issue is being caused by something around the IC, seeing as the...

Re: Dell U2311H, display turns off after some time, requires unplugging to reset



Sure thing, I added a few pics of the logic board to that gallery -> [url]http://brettb.net/dellmonitor/[/url].Re: Dell U2311H, display turns off a...onitor/[/url].Re: Dell U2311H, display turns off after some time, requires unplugging to reset



Sure thing, I added a few pics of the...

Re: Dell U2311H, display turns off after some time, requires unplugging to reset

Some more pictures [URL="http://brettb.net/dellmonitor/"]http://brettb.net/dellmonitor/[/URL] - that large .22ohm resistor seems to have a bit of a surface defect, but it measures ok (.3-.4ohms, I only have a standard DMM which won't do low resistance, but that seems about right with the leads).Re: Dell U2311H, display turns off after some time, requires unplugging to reset

Some more pictures [URL="http://brettb.net/dellmonitor/"]http://brettb.net/dellmonitor/[/URL]

Re: Dell U2311H, display turns off after some time, requires unplugging to reset



Sure thing, I'll take some more pics after my camera batteries charge - I'm not aware of any power brick for this monitor - I believe the socket there is for a speaker bar....

I've got a Dell U2311H, which will operate for some amount of time, and then turns off and becomes completely unresponsive (no LED, no voltage on the power supply lines) until you unplug it for awhile, and plug it back in.

A picture of my board:



What I've done:

1. Checked all the caps with an esr meter, they measure fine (but presumably could still be the issue with the below symptom?)

2. Tracked what is happening, but not the actual cause, down to the IC protection circuit (tea1530):

The voltage on the...

Re: New Members - please post your introductions here

Hey all, just trying to fix an LCD that I'm having problems with - this site looks like a great resource!