laptop motherboard soldering - Page 1
Forum section: electronics / beginners

author: ShadyK
author_rank: Contributor
timestamp: November 06, 2013, 03:53:46 pm
content: Hi again everyonebecause i got such good and helpfull responses from my last post. I would really appriciate some help again please. I want to add LEDS to my laptol case and keyboard. The case modding is not a problem. Its knowning 100percent were to put the cables. Will i just test the connections to my battery connector and run the cables of there with a transistor on the negative? Thanks for the help in advance.

author: Terabyte2007
author_rank: Frequent Contributor
timestamp: November 06, 2013, 04:11:06 pm
content: What are these LEDS for? Power, HD,

author: ShadyK
author_rank: Contributor
timestamp: November 06, 2013, 04:55:59 pm
content: I would have leds to illuminate my keyboard and then just tk moddified my casing

author: Simon123
author_rank: Regular Contributor
timestamp: November 06, 2013, 05:17:46 pm
content: Why dont you solder it to usb?

author: G7PSK
author_rank: Super Contributor
timestamp: November 06, 2013, 05:24:05 pm
content: Most laptops will have an unused USB port on the motherboard that you could use without having to use one of the physical port outlet sockets, have a look at the laptop schematic or circuit diagram.

author: ShadyK
author_rank: Contributor
timestamp: November 06, 2013, 05:46:05 pm
content: There will be about 6 leds in total will i have to use a transistor ? And i am a noob at this so would it be easier to solder to usb?

author: Terabyte2007
author_rank: Frequent Contributor
timestamp: November 06, 2013, 06:19:41 pm
content: You should not need a transistor, but you will need some current limiting resistors depending on where you pick up the Vcc. Coming off the USB will give you about +5V or slightly less depending on your USB driver chip. Keep in mind that the USB will be limited in current (Ranging from apropx. 300mA - 500mA) so keep this in mind when you spec the LEDS and if you plan to still use this port for devices. Personally, I would come off the main +5V rail or regulated output but this depends on your skill level. If you want to get really crazy, you could add some logic and watch for a keypress then turn on the LEDS for a predetermined amount of time with a timer chip, then turn them off again!

author: Simon123
author_rank: Regular Contributor
timestamp: November 06, 2013, 07:15:12 pm
content: Will you have a switch, so you can turn leds on and off?But be carefoul, not to desolder any smd caps and resistors while doing this.

author: ShadyK
author_rank: Contributor
timestamp: November 06, 2013, 07:25:46 pm
content: Oooo like a mobile phone keyboard thats got me intreaged how would i go about doing that then? This is my practising ya see im just starting out so i want as much expeirence as possible

author: Simon123
author_rank: Regular Contributor
timestamp: November 06, 2013, 08:42:45 pm
content: What type of laptop do you have?

author: ShadyK
author_rank: Contributor
timestamp: November 06, 2013, 09:29:49 pm
content: Well its a pooh one because i dont eant to brake my proper one its a samsung r519

author: Simon123
author_rank: Regular Contributor
timestamp: November 07, 2013, 05:40:06 am
content: Thatl be hard in thin laptop like that.You could try el wire(pop the buttons of and lay the wire around), but the inverter is pretty big.

author: ShadyK
author_rank: Contributor
timestamp: November 07, 2013, 12:09:41 pm
content: Im still a little bit new so could you explain that a bit more for me. Could i not just run the wires around the casing to where i want the leds to sit? And hot glue the leds in place? Or would that not work?

author: amyk
author_rank: Super Contributor
timestamp: November 07, 2013, 12:25:12 pm
content: Be careful with EL wire, high voltage high frequency can cause EMI issues especially with things like the trackpad.

author: Simon123
author_rank: Regular Contributor
timestamp: November 07, 2013, 03:15:32 pm
content: You could use leds, but for this small keyboard itll be tight fit.And how would you get wire from inside to outside? You proably wont drill holes in keyboard?

author: ShadyK
author_rank: Contributor
timestamp: November 07, 2013, 11:54:14 pm
content: Yeah thats what my problem is going to be the case modding but i can fathum that out it was mainly the wiring and the powering thats all because if my keyboard is too thin i was going to mod the top part with leds in too.