Can I Solder a usb-c female to a dc output?

Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
I am trying to make a second monitor out of my old laptop screen. I have the control board already and it works, but I want to make it more compact. The screen takes a 12V power supply to power it, but I want to make it powered by plugging it into the USB port on the computer. My idea was to get a usb A male to usb C male cable on the computer and plug that into a Usb C female to AC adapter.

I’ve been looking for integrated power delivery cables but I’m having a really hard time finding one that’s 12 Volts. I know I can’t just take a 12V adapter, cut the plug, and replace it with a USB C Female bc the voltage would be too low. Can I take a usb c male to dc and cut the male end off and replace it with a usb c female or does that not work?

Does anyone know where I can find the integrated cable? I’d rather not solder since I have no experience with soldering nor do I have a soldering iron
 
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KeithWalker

Joined Jul 10, 2017
2,027
I am trying to make a second monitor out of my old laptop screen. I have the control board already and it works, but I want to make it more compact. The screen takes a 12V power supply to power it, but I want to make it powered by plugging it into the USB port on the computer. My idea was to get a usb A male to usb C male cable on the computer and plug that into a Usb C female to AC adapter.

I’ve been looking for integrated power delivery cables but I’m having a really hard time finding one that’s 12 Volts. I know I can’t just take a 12V adapter, cut the plug, and replace it with a USB C Female bc the voltage would be too low. Can I take a usb c male to dc and cut the male end off and replace it with a usb c female or does that not work?

Does anyone know where I can find the integrated cable? I’d rather not solder since I have no experience with soldering nor do I have a soldering iron
USB cables are for supplying 5VDC to devices. It is not a good idea to to use them for 12VDC because you will eventually accidentally plug the 12V source into a 5V device and destroy it. The best way would be to build a 5V to 12V invertor into your monitor and power it with 5V from a USB source.
https://www.aliexpress.com/item/100...9#834_4452#5108#23442#697_4452#3564#16062#427
 

Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
How will I plug the ac adapter into the USB port? I must have done a bad job explaining because that makes zero sense. It’s a FEMALE usb c end soldered to an AC male adapter. You can’t plug it into the wrong device... the only male-male connection is the separate USB A to USB C cable, which are incredibly common and pose no risk of plugging into the wrong device. Does that clarify anything? Also waiting 30-50 days shipping is not ideal
 

Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
You are on your own on this one. I can not offer any further advice. Good luck!
You seem knowledgeable enough to offer more advice. Are you offended or something? We’re both saying the same thing dude. Take a signal and convert with a PD controller. I’m asking about integrated Pd controllers
 

Yaakov

Joined Jan 27, 2019
3,735
I am trying to make a second monitor out of my old laptop screen. I have the control board already and it works, but I want to make it more compact. The screen takes a 12V power supply to power it, but I want to make it powered by plugging it into the USB port on the computer. My idea was to get a usb A male to usb C male cable on the computer and plug that into a Usb C female to AC adapter.

I’ve been looking for integrated power delivery cables but I’m having a really hard time finding one that’s 12 Volts. I know I can’t just take a 12V adapter, cut the plug, and replace it with a USB C Female bc the voltage would be too low. Can I take a usb c male to dc and cut the male end off and replace it with a usb c female or does that not work?

Does anyone know where I can find the integrated cable? I’d rather not solder since I have no experience with soldering nor do I have a soldering iron
I am finding it exceedingly difficult to follow your narrative. Could you draw a picture to clarify things?
 

Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
Two cables: one is male USB A (purple) to male USB C (green). Second cable is female USB C (blue) to DC output (red). First cable carries 5V from a USB port. Second cable converts the signal to 12V.

FE84B420-63F9-4D67-948D-8FABF7DD3754.png

I need to use a PD controller to step up the signal to 12V. The second cable is really hard to find. I want to know if I can make my own cable by taking a male USB C to DC cable and cutting off the male part and soldering on a female USB C port to replace it. Does this clarify anything or do I need a better picture?
 

KeithWalker

Joined Jul 10, 2017
2,027
I am trying to make a second monitor out of my old laptop screen. I have the control board already and it works, but I want to make it more compact. The screen takes a 12V power supply to power it, but I want to make it powered by plugging it into the USB port on the computer. My idea was to get a usb A male to usb C male cable on the computer and plug that into a Usb C female to AC adapter.

I’ve been looking for integrated power delivery cables but I’m having a really hard time finding one that’s 12 Volts. I know I can’t just take a 12V adapter, cut the plug, and replace it with a USB C Female bc the voltage would be too low. Can I take a usb c male to dc and cut the male end off and replace it with a usb c female or does that not work?

Does anyone know where I can find the integrated cable? I’d rather not solder since I have no experience with soldering nor do I have a soldering iron
Two cables: one is male USB A (purple) to male USB C (green). Second cable is female USB C (blue) to DC output (red). First cable carries 5V from a USB port. Second cable converts the signal to 12V.

View attachment 242343

I need to use a PD controller to step up the signal to 12V. The second cable is really hard to find. I want to know if I can make my own cable by taking a male USB C to DC cable and cutting off the male part and soldering on a female USB C port to replace it. Does this clarify anything or do I need a better picture?
Yes, you need a much better picture. This one just creates more questions.
What exactly is the "PD controller" and how is it connected?
 

Yaakov

Joined Jan 27, 2019
3,735
This simply will not work. The boost converter that would be needed would not have enough current from the USB port to supply sufficient current at 12V to power a display.

The computer's USB port produces, at most, 2.1A, boost converters are not 100% efficient, to go from 5V to 12V you will max out at maybe 500mA.

EDIT: And the computer port may only provide as little as 500mA itself, making almost no current available at 12V.
 

BobaMosfet

Joined Jul 1, 2009
1,896
I am trying to make a second monitor out of my old laptop screen. I have the control board already and it works, but I want to make it more compact. The screen takes a 12V power supply to power it, but I want to make it powered by plugging it into the USB port on the computer. My idea was to get a usb A male to usb C male cable on the computer and plug that into a Usb C female to AC adapter.

I’ve been looking for integrated power delivery cables but I’m having a really hard time finding one that’s 12 Volts. I know I can’t just take a 12V adapter, cut the plug, and replace it with a USB C Female bc the voltage would be too low. Can I take a usb c male to dc and cut the male end off and replace it with a usb c female or does that not work?

Does anyone know where I can find the integrated cable? I’d rather not solder since I have no experience with soldering nor do I have a soldering iron
@TheGuyMain This is premised on using 5VDC USB to 12VDC Display. If the Display requires AC. that is a whole different problem.

If DC to DC, then: You have to answer the most important question- what is your screen rated at for wattage? Without knowing the voltage and the wattage, we cannot determine the current, or whether or not a DC;DC Boost converter would even work.

For example, let's say we make a 5 to 12V DC : DC BOOST Regulator using the ubiquitous MC34063A - As shown, it must be able to pull at least 1.475A from the USB port to get to 3W for the display (I just guessed your display needs 3W). That's why we need to know the Wattage rating of your display.

1624907203647.png

The 7.378W is what the IC has to handle to do the above.
 
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Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
Yes, you need a much better picture. This one just creates more questions.
What exactly is the "PD controller" and how is it connected?
if you don’t know what the component is, drawing a picture of it won’t help lol A power delivery (PD) controller is what you linked to me. It controls the delivery of power. I am talking about integrated PD controllers. They come inside of the cable. Think of them as adapters. They connect the same way any other adapter connects: it has one thing that goes in and a different thing that goes out. The picture perfectly describes what goes in and what goes out of each cable. It’s even color-coded. Maybe try reading it now
 
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Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
This simply will not work. The boost converter that would be needed would not have enough current from the USB port to supply sufficient current at 12V to power a display.

The computer's USB port produces, at most, 2.1A, boost converters are not 100% efficient, to go from 5V to 12V you will max out at maybe 500mA.

EDIT: And the computer port may only provide as little as 500mA itself, making almost no current available at 12V.
Thank you. This helps a lot. So is the only option to plug into a 120V wall socket like I am now, or is there any way to get enough power from the computer (without connecting directly to the power supply or something)? Also I think it’s worth noting that this guy powers his screen with a usb connection

 
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Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
@TheGuyMain This is premised on using 5VDC USB to 12VDC Display. If the Display requires AC. that is a whole different problem.

If DC to DC, then: You have to answer the most important question- what is your screen rated at for wattage? Without knowing the voltage and the wattage, we cannot determine the current, or whether or not a DC;DC Boost converter would even work.

For example, let's say we make a 5 to 12V DC : DC BOOST Regulator using the ubiquitous MC34063A - As shown, it must be able to pull at least 1.475A from the USB port to get to 3W for the display (I just guessed your display needs 3W). That's why we need to know the Wattage rating of your display.

View attachment 242349

The 7.378W is what the IC has to handle to do the above.
How do I find out the wattage of the screen? It’s from a gateway nv55 series laptop but that’s about all I know
 

Yaakov

Joined Jan 27, 2019
3,735
Thank you. This helps a lot. So is the only option to plug into a 120V wall socket like I am now, or is there any way to get enough power from the computer (without connecting directly to the power supply or something)? Also I think it’s worth noting that this guy powers his screen with a usb connection

If your computer has a USB C connection, it could do the job. A USB 3 connection can't.
 

Yaakov

Joined Jan 27, 2019
3,735
If I have a powered port (it’s a desktop) could it work?
The most you will get is about 2A and that's probably not enough to do the conversion with enough current. But, to know for sure you have to find out what the current rating of your computer's port is, and what the current requirements for the display are.

Then you can work out whether a boost converter is possible.
 

KeithWalker

Joined Jul 10, 2017
2,027
if you don’t know what the component is, drawing a picture of it won’t help lol A power delivery (PD) controller is what you linked to me. It controls the delivery of power. I am talking about integrated PD controllers. They come inside of the cable. Think of them as adapters. They connect the same way any other adapter connects: it has one thing that goes in and a different thing that goes out. The picture perfectly describes what goes in and what goes out of each cable. It’s even color-coded. Maybe try reading it now
That explains the misunderstanding. To me, a "PD controller" has always been a "Proportional-Derivative controller" which is a control loop mechanism employing feedback.
 

Thread Starter

TheGuyMain

Joined Jun 28, 2021
21
The most you will get is about 2A and that's probably not enough to do the conversion with enough current. But, to know for sure you have to find out what the current rating of your computer's port is, and what the current requirements for the display are.

Then you can work out whether a boost converter is possible.
ok so what if I used two USB ports at once and combined their power. Would that be enough to power a 12V screen?
 

Yaakov

Joined Jan 27, 2019
3,735
ok so what if I used two USB ports at once and combined their power. Would that be enough to power a 12V screen?
It is not the voltage that's a problem it's the current. Without information about how much current the ports produce, the efficiency of the boost converter, and the current requirements of the display that question can't be answered without anything but a guess.

"Maybe."
 
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