Dell 2007WFP Won't Power On

[komix]

In my monitor the display S-PVA Samsung LTM201U1 is installed, it is powered by a voltage of 5v to 12v in where to use?

[ibjeepin]

Re: Dell 2007WFP Won't Power On

ss

Thanks for that budm. Lord knows I have no idea, but I can't give up yet. I have some basic questions if you want to take a crack at them.

Please correct me if I am wrong and point me in some direction. I need to do some crawling before I can walk.

On my application, is my power board's main function to take 120V AC and supply 19V DC to the other boards (USB/DC, logic and inverter)?

And is one of the jobs of the USB/DC board to use the 4 "buck regulators" to make 3.3V, 5V, 12V and some other voltage available for use on that and the other boards?

I feel the power button goes to the logic board to get things started, but can you explain a little what happens?

Also, I have made a little sketch to try to better understand the "buck regulators". I borrowed your previous drawing as a start and would appreciate corrections and comments. If it is not valid, feel free to tell all not to use it. I am not claiming it to be correct.

MEB thanks for the schematic!

My 2007WFB rev a00 had Q2 populated as well.

Q2 is 5V output and its switched on via a signal from the cpu.
It is used to power the LCD and it goes straight trough pins 9-10 to the Logic board and straight to the LCD harness plug. Q2 is driven by the 2OUT of U3 TL1451A via a signal line through the connector to the logic board, i forget which one.

When the monitor goes to sleep the 5V is shut down so if you test that board out of circuit the voltage will not be present.

Another note for all the 12V output for the speaker is switched off until you plug something into the coax connector. This send a switch signal to the U4 TL1451A to turn the mosfet on via pin 2OUT.



Thanks to everyone most importantly to budm for his work. In my case it was the 2.7k resistor on U4 TL1451.

The very last thought is; there must be a reason they squirted the silicon on that one of four TL1451 pwn controllers. My unanswered question is why? Heat? Insulation? Anyone?

[ibjeepin]

Re: Dell 2007WFP Won't Power On

In my monitor the display S-PVA Samsung LTM201U1 is installed, it is powered by a voltage of 5v to 12v in where to use?

5V via Q2 on the USB board. Thats all it uses