Re: Dell U2715H no power
Update time.
Got the new main IC, replaced it and it gets power, I get backlight, laptop detects it at full resolution, I get the 5V for lcd power(not 12V as expected), but the screen only flashes colors (red, green, blue, white, gray). After some research found out it is Dell burn in mode and I can not disable it. Tried all button combinations from google, nothing works, so yeah. One funny thing is I have no power indication light, might be my BGA soldering, but the power button responds, can't really check for other buttons since I can't really do...
bangaham
Member
Last Activity: 12-24-2024, 02:34 AM
Joined: 09-21-2019
Location: Sveti Ilija
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Re: How does optical alignment work?
Thank you very much!
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Re: How does optical alignment work?
Hi again,
if it's not too much trouble, could you measure the size of the cube?
Doesn't need to be super precise.
Thanks...Leave a comment:
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Re: How does optical alignment work?
It helps a lot. ThanksLeave a comment:
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Re: How does optical alignment work?
That would be great, thanks. Hope you enjoy your station....Leave a comment:
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How does optical alignment work?
Hi,
I see a lot of BGA Rework stations that offer optical alignment and I'm curious about how it works.
I guess you need two right angle prisms placed in a cube with a mirror on one side like in the attached picture (sorry paint is all I had) but what determines the image size you can see and how does the camera that captures the image work?
I tried googling but can nowhere find a diagram, so if anyone could draw one in paint or whatever, or has some info I'd be thankful.... -
Re: Dell U2715H no power
I measured all already and all seem good, only C733 has a lowish resistance to ground(around 20 ohm) but I removed it and measured it still had that resistance (could be normal but since I don't have schematics I have no clue what the line is and what it does).
I bypassed the whole regulator, added my own buck converter from input(19V) and set it to 12V and plugged in the screen and still nothing so I assume the main ic is just dead because sometimes I can't turn it on, sometimes doesn't recognize laptop.
Next I'm just gonna replace the...Leave a comment:
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Re: Dell U2715H no power
Hi, thanks for the reply,
I took more time with the board and all the voltages are present except the 12V which powers the LCD controller board. Unfortunately the switch IC has no datasheet (the only writing on the IC is AIV7JA) it has input voltage (19.2V) but
since I don't have a datasheet or main pcb schematic I can't determine if there is an enable signal coming from the main ic or the ic is just dead.
If anyone has any idea what the IC model is or has a datasheet I'd be thankful.
Added pictures of...Leave a comment:
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Dell U2715H no power
Hello,
so I got this Dell U2715H monitor that originally wouldn't turn on. I took it apart and started diagnosing. The power supply is supposed to give 20V (printed on silkscreen) and the output is 19.1V stable, all capacitors look good and are Rubycon brand so I assumed that was ok (don't have ESR meter to verify).
I then proceeded to the main board. Plugging in the power supply nothing happens, front panel touch buttons do nothing, laptop doesn't detect it via HDMI, but the main heat sink gets warm. Don't have the schematics but found the main voltage rails (5V, 3.3V,... -
Re: New Members - please post your introductions here
Hello guys,
I'm 22, electrical engineering student interested in electronics repairLeave a comment:
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