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External 2nd monitor - hot to power ?

Hello everyone, i need your help on some of my questions before i will lunch myself into this project.

 

First of all im gonna build my self an external screen for work, it really helps me sometimes when i have a second screen to work on.

 

The screen i recovered was from an old toshiba satellite L300-17L. And i found on ebay the controller board i have to buy for it to work:

https://www.ebay.fr/itm/142913931883?hash=item2146558a6b:g:SwUAAOSwj~9bfi-M

 

My work laptop is a Dell Latitude 5580.

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My question: is there any way to power the screen from on of the USB ports with a cable like this one ( amazon link ) or will there be no enough power coming from the usb ports?

 

I know i can get a DC plug to power the screen but my goal is to not carry another power adapter and i would like to have all cables connected to the llaptop for power and hdmi output.

 

Thnx to everyone in advance

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38 minutes ago, astrit_arsllani said:

is there any way to power the screen from on of the USB ports with a cable like this one ( amazon link ) or will there be no enough power coming from the usb ports?

Not sure if that will work. But I think USB is limited to 5 volts. So what ever device you need to run has to be able to use 5v. Im also pretty sure most of the portable monitors on Amazon are powered via USB. 

I just want to sit back and watch the world burn. 

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The lcd display uses fluorescent lights to do backlight, so you need that CCFL inverter board to convert 8v .. 20v (maybe higher voltage is supported, depends on model)  to what the backlight needs (hundreds of volts).

 

So if you want to power it from usb, you would need to get a step-up converter / boost converter to boost 5v to around 10-12v - some will work with as little as 8v, some with at least 10v or 12v like I said.

Can't say how much power the backlight will use, could be a significant amount, like 5-10w, maybe even more.

 

The display board will usually have a power connector that will have 5v, 3.3v and sometimes 12v  -  12v is often there to power audio amplifier, if the displayboard has headphones output or for built in speakers. Most of those universal display boards will function without 12v connected to them, but 5v is a must.  3.3v you would also have to provide using either a linear regulator or a step-down/buck converter you can buy for a couple of dollars.

Some universal display boards produce 3.3v from 5v on the board using a dc-dc converters, others expect you to provide it.

 

The laptop.... I suppose will give you at least 5v 0.1A on the usb ports. It may give you 0.9A or 4.5w if it's a usb 3.0 port, but usually a laptop will complain if some device pulls more than 0.1A without sending the usb messages that it wants the maximum power.

 

If you make some usb cable which takes power from two usb ports, you may be able to pull around 8-10 watts without the usb ports shutting down, and with some low-medium brightness maybe it's low enough power consumption to work..

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I just found out that my laptop has a usb type C PD port.  Will that be enought te power the external 2nd screen ( at the ebay page for the controller it was noted that it requires 12V 4A power)  ???

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