Dell 2407WFPB bad inverter xformer Part 1

[budm]

Have about 1/2 hour of spare time before going to the gym just to find out why it has 2 seconds to black:
One bad inverter transformer.
I will have to show in multiple posts due to large amounts of pictures.
See them at Photobucket also:
http://s807.photobucket.com/albums/y...ll%202407WFPB/

[budm]

Re: Dell 2407WFPB bad inverter xformer Part 2

More pictures.

[tom66]

Re: Dell 2407WFPB bad inverter xformer Part 1

The error often occurs if you upload the pictures but it takes too long and the token expires for some reason... maybe try 5 per post at a time or just link to your Photobucket? (very useful pictures you've got there)

[budm]

Re: Dell 2407WFPB bad inverter xformer Part 3

More pictures.

[retiredcaps]

Re: Dell 2407WFPB bad inverter xformer Part 1

Using Fluke's autohold would make your life easier to take photos.

I see this lcd uses the same type of USB board as the Dell 2007FPb.

[Obliterous]

Re: Dell 2407WFPB bad inverter xformer Part 1

were you able to source a new inverter xformer, or did you have to replace the entire board?

I have the same model monitor with the exact same problem.

(sorry for the necro bump, but most relevant thread)

[zombielinux]

Re: Dell 2407WFPB bad inverter xformer Part 1

Apologizing for the necro bump, but I've found that Pin 3 (the green wire) on CN702 is the brightness control line. It appears to go from 0v to whatever the reference voltage on Pin 1 (blue) is.

Further investigation shows that the 20 pin soic package is an analog to pwm brightness controller.
(Datasheet here: http://pdf.datasheetbank.com/datashe...O2Micro/0Z964S)

Pin 3 on that chip seems to be related to the presence of voltage on pin 1, and pin 14 seems to be related to pin 3 on the connector.

My guess is the dimming voltage is found via the comparitor (the odd 8 pin soic package) and then fiddled with through the rest of the circuitry.

Regardless, I feel this is important information and should be known for future reference.