Dell E207WFPc

[PlainBill]

Re: Dell E207WFPc

I understand. Hope these pics will help.

I've marked three devices. The first two (upper left and mid-left) are probably voltage regulators. Using one of the mounting holes as a ground point, what are the voltages on each pin? And what is the part number of the one without a thermal pad?

The one on the right may be the key to the problem. What is the identifier on that IC?

PlainBill

[killian6pk]

Re: Dell E207WFPc

Readings. On Ac V

Regulator with Thermo Pad (Upper Left)
Pin 1 = 46.6v
Pin 2 = 46.7v
Pin 3 = 46.7v

Middle Left Regulator
Lettering on part: AZ1117D
1.8E1
70IN19
Pin 1 = 46.7v
Pin 2 = 46.7v
Pin 3 = 46.6v

Small Part on right
Lettering on part: 6910P First number could also be an 8

Pin 1 = 47.7v
Pin 2 = 46.6v

Data Sheet for AZ1117D: http://www.datasheetarchive.com/AZ11...datasheet.html

[alexanna]

Re: Dell E207WFPc

Readings. On Ac V

Measure DC voltage

[killian6pk]

Re: Dell E207WFPc

I tried DC to start with and the readings had a minus sign and bounced all over the place so that I could not get a fix on the number. I will try it again.

[killian6pk]

Re: Dell E207WFPc

I was able to get readings this time by moving my black probe to a ground screw hole on the power board instead of on the video board. The numbers still jumped around a good bit but finally settled down so that I could get a reading.

Regulator with Thermo Pad
Pin 1 = 339.6mv
Pin 2 = 335.1mv
Pin 3 = 336.6mv

Middle Left Regulator
Pin 1 = 334.8mv
Pin 2 = 336.2mv
Pin 3 = 335.8mv

Small IC on Right
Pin 1 = 336.4mv
Pin 2 = 336.4mv

[killian6pk]

Re: Dell E207WFPc

Just to clarify the numbers above were on the DC scale.

[alexanna]

Re: Dell E207WFPc

Just to clarify the numbers above were on the DC scale.

Verify you are still getting 5 volts on pins 7 and 8 on the power supply, and then use the same ground to measure the regulators.

[killian6pk]

Re: Dell E207WFPc

When I measured again just now I got 333.8mv on both pin 7 & 8. I checked the fuse and it is still 0.1ohm. What should I do now?

[retiredcaps]

Re: Dell E207WFPc

When I measured again just now I got 333.8mv on both pin 7 & 8.

Something has changed. 5V was present and the voltage regulators were all fine back on page 1 of this thread.

[killian6pk]

Re: Dell E207WFPc

Yes, but the only thing I have done is check readings with the power on and the power board and main board connected. I don't know what could have changed unless connecting to power burned something else out. That's why I checked the fuse. I don't know where to go from here.

[alexanna]

Re: Dell E207WFPc

Are the boards screwed down to the metal chasis,or they Laying loose

[killian6pk]

Re: Dell E207WFPc

They are loose on my workbench. If I screw them down into the metal housing they are upside down and I can't get at the front side of the boards.

[alexanna]

Re: Dell E207WFPc

I suspect you do not have a proper ground for your DVM.
There should be a wire in the conector from the P/S to the siginal crad that is ground.
See if you can locate it and use that for the negitive lead on the DVM.

[killian6pk]

Re: Dell E207WFPc

I will try that.

[killian6pk]

Re: Dell E207WFPc

Using the ground wire like you said. The two 5v pins show 5.07v. The 3 places that Bill wanted me to check are as follows:

The regulator with the foam on top:
Pin 1 = 0.9mv
Pin 2 = 3.295v
Pin 3 = 5.07v

Regulator on Middle Left of board:
Pin 1 = 0.9mv
Pin 2 = 1.799v
Pin 3 = 3.294v

Small IC on Right Side:
Pin 1 = 0.9mv
Pin 2 = 3.033v

[alexanna]

Re: Dell E207WFPc

Using the ground wire like you said. The two 5v pins show 5.07v. The 3 places that Bill wanted me to check are as follows:

The regulator with the foam on top:
Pin 1 = 0.9mv
Pin 2 = 3.295v
Pin 3 = 5.07v

Regulator on Middle Left of board:
Pin 1 = 0.9mv
Pin 2 = 1.799v
Pin 3 = 3.294v

Small IC on Right Side:
Pin 1 = 0.9mv
Pin 2 = 3.033v

Good, the voltage regulators look OK
Hopefully PlainBill will continue with his thoughts.

[killian6pk]

Re: Dell E207WFPc

Thanks for the suggestion on the grounding.

[PlainBill]

Re: Dell E207WFPc

I was hoping that the small IC was a reset controller, but the part number seems to indicate otherwise, and the polarity of the signal is wrong. Whoops!!! The IC I was indicating has THREE leads. Recheck, please.

PlainBill

[killian6pk]

Re: Dell E207WFPc

That was my fault I checked the proper chip, but forgot to check the top soldered tab. I go check that now.

[killian6pk]

Re: Dell E207WFPc

Here are the readings on the small chip on the right.
Pin 1 = 0.8mv
Pin 2 = 3.033v
Pin 3 = 5.07v

Hope this helps.