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Help connecting a Led strip to laptop power source. Answered

Hi all,

I want to illuminate my laptop keyboard and since the name of the device is LAPTOP meaning it is a mobile device, the tutorials on Youtube were not that promising ... and trust me I searched a lot.

I work at a lighting company, we have tons of led stips ... the lowest is a 12V 7W LED strip and that's 7W per meter ... the closest CUT-HERE mark on the strip involves 6 SMD LEDs which is enough for me, this strip doesn't overheat, I put my finger on it. 

The question is it possible to solder these 6 LEDS to the 12V DC power jack of the laptop or the USB power (+ / -) port ( on the mainboard ) .... as for the strip itself, I can install it on the Laptop Chassis, not necessary inside te Chassis in a very neat way.

can it be done? is there any risk on the laptop ? .... will the USB still be usable ? ( again I don't want to plug a USB cable to power the LEDs I want to solder on the USB port on mainboard)

Thank you

Discussions

what about this ? ... can I remove the USB plug and solder it on the USB port ? it says 5V DC

http://www.ebay.com/itm/50-100-200cm-3528-SMD-LED-Strip-Light-TV-Background-Lamp-Waterproof-USB-Cable-/131762041291?var=&hash=item1eada131cb:m:md4GtFYZTa0EPzNstx-0XaQ

I don't want this, already have one, the less hassle the better, these are ineffective. why do I want to buy a male USB port ? this is going off topic. The only thing I want on the surface of the laptop is the 6 LEDs ...

You need a male USB plug so you can plug it into the female USB port of the computer, to get 5V. Hope this helps.

seems that most laptop chargers provide 19V not 12V :-(
@Yonatan24, I don't even know where to solder this power booster. I thought I can solder directly on USB port

Laptop charger, or USB port?

You need to solder a male USB plug to the input of the converter. Do you know how to do this?

is there any port on the laptop that could supply 12V ? ... sorry suggestions are popping through my head one after another

Guys Guys Guys, in my first post, I mentioned that I will only use 6 LEDs of the whole strip, not even 1 meter long,a 6 LEDs are only about 10 cm.
@Antzy Carmasaic, 6x20mA = 120mA, can I still use the USB 2.0 port ? ... also the soldering will be from the motherboard side on the USB port.

The power Jack isn't fed electricity by battery too, even if there's no charger plugged ? in other terms isn't all the motherboard receiving electricity from the battery ?

can't a USB power 6 LEDs even if they were 12V and the USB is only 5V ?? is a power buck necessary ?

I appreciate your input but please put in some more effort and help me achieve it.

PS: I bought a cheap 100$ acer timeline with celeron SU-2700 to use it as a test bed, if it works, I will apply it on a better machine. So if something happens, I won't be sorry for it.

Thanks. so

As you mentioned, you need 7W to light up a meter. So assuming you are using 30 LEDs per meter strip, each LED is consuming about 20mA(which is perfect!). This is important as you will need to know how many LEDs you can light up safely.

To pull power for it, you mention you are considering soldering to USB's power terminals. You will be unable to use that USB port as a majority of the current will be going to the strip instead of the peripheral connected to USB. You'll be able to pull 500mA from it, but might be limited to only 100mA depending on your laptop(http://electronics.stackexchange.com/questions/549...) Also, you'll need a buck-booster as Yonatan24 mentioned

Connecting to the laptop charger port, is a better option if it provides 12V. Light will only glow when charger is connected, but chances of anything going wrong with motherboard are greatly reduced.

does each LED get 12v? Or are they in series such that in a circuit of 12 LEDS (or whatev #) each one gets 1 v?

yes the leds will be cut from a 5 meter standard strip LED roll. I want to cut up to 6 LEDs from the strip.

led-strip-ultra-bright-24vdc-14-4w-m-ip65-waterproof-71d.jpg