Powering 5050 RGB LEDs from an arduino

[Viktory2k1]

Hi
I want to test a 5M strip of RGB LEDs using and Arduino, the leds are 12v and I can get the sketch easily and I think but the breadboard uses some type of transistors(tip120) to boost the voltage and to power it externally. The transistors I have on hand are KA7905 and some CTB34 with different suffexes on them. Also C4139 transistors but those are huge and these are old as I de-soldered them from some old pc PSU's and some may be outdated(these things were 20+ years old but worked). I have the first ones mentioned in the breadboard with 180 ohm resistors going to the far right terminals. At least thats what I think they are. I will look for some diagrams to see which terminal is what but I think the collector is the one on the right.
I think this is what I am trying to do. Is this right? Base left, emitter middle, collector right.

 

[Harald Kapp]

The KA7905 is not a transistor, but a three-terminal 5 V voltage regulator.
CTB34 is a Schotttky-Diode, not a transistor either.

The TIP120 on the other hand is an NPN power darlington transistor.

As I said before in another thread, your method of trial and error is not getting you along. You should really start with some theory. Looking up a datasheet of the components you are going to use is part of that effort.

 

[BobK]

And if they were transistors with the pinout you described, the collector and emitter are reversed. The emitter should be at ground and the collector connected to the R, G and B lines.

Check out this resource on using transistors as switches:

https://www.electronicspoint.com/resources/using-a-bipolar-transistor-to-turn-a-load-on-and-off.30/

Bob

 

[Viktory2k1]

OK, thanks. I will see what else I de-soldered. I know I got some transistors. As Harold said, I am going nowhere fast.

 

[Viktory2k1]

OK NT407F. I know those are transistors and I have 2 but let me dig around. Had a crisis last night or rather 2 nights ago. I will tell the story if I get 3 transistors.ok, C25M? not sure about that one, very hard to read 02012F.
One of these has to be a transistor. I de-soldered these out of old pc psu's. CT34M, C4139 1D.
I know some of these have to be transistors because I googles the numbers and I had 3 of them with the numbers provided but my cats scattered them all over the place.

 

[Viktory2k1]

Another CTB34M, got 2 of those, 2 of these C4139. 2 NT407F. 020-12f, DBB2 with NEC at the top could be DB82 but too small to see even with a magnifing glass. 1 KA7912 and 1 KA7905.

 

[Viktory2k1]

Theres gotta be some transistors in this mess some where. How about a blueray player?

 

[Viktory2k1]

I have seen that schematic before but need the transistors, I know I gotta have 3 around here.

 

[Viktory2k1]

What happened last night, everything is fine so far, Is I am building a virtual pinball machine, I am trying to recycle old PC components and 1 happens to be a LGA775 MOBO that I liquid cooled back in the day. I am now realizing that the EL hoses are becoming deteriorated. I don't care about typos. I jumped the PSU terminals to see which way the fans blow and they spooled up and as I was feeling for air which I am still not sure which side it was blowing from, a gyser of coolant was flying out 2 inches from a hose that broke off the heatsink for the CPU so I quickly disconnected the power and ran out of the room to get paper towel to soak up the mess, when I returned, I found my 2 cats licking at the extended life antifreeze like it was caviar so I gently moved them out of the way and soaked it up. Today, both cats are fine and my carpet, which I layed myself is fine. I bought new hose and want to try to hook this up again. Due to health conditions, I can no longer do projects for other ppl fpr money so I do what I can without meds, lastnight I did take them and was on here to learn about my "transistors" which I know now were voltage regulators but I googled 3 numbers and at least 3 were transistors which is all I need for the breadboarding to test the RGB LED and was basically told I was too stupid to be on this site. Sorry, this is new to me and can't find my own a,, with 2 hands and a flashlight. I was just P.Oed because I am not one of those who joins a forum, get an answer, and quits. I am not like that. I moderate 3 forums and not once did I tell someone that they were too dumb to understand this. I was not told that in so many words but if need be, I will look elsewhere for a way to learn this stuff. I do not have a higher education then highschool and worked as a garbage truck mechanic since 19 and after 25 years, I like to think I know a thing or two. I thought I scored when I found 3 transistors but I am now told that all I found were voltage regulators, I know I have 3 transistors. I looked them up and am having difficulties doing so now as my health declines. After Monday, I will have my miracle shots and then have a conference call with 2 lawyers and a judge and after that, I will be on top of this better. No disrepect to members I tried to help, I was just trying to use laymans terms for things and some succeeded with their projects.
OVER AND OUT.

 

[Viktory2k1]

I did look up the data sheets and found some were obsolete and some wete transistors, I will look again.

 

[Viktory2k1]

Thank you BOBk, I also noticed it says to power the Arduino so VIN is the output voltage? OK, I have a VIN on the power side but what does it mean to power it so vin is output voltage? The diagram I showed before shows the 12v source going directly to the breadboard. I just want to see if these things work for the pinball. It will not have an Arduino on it but would like to learn this stuff.

 

[BobK]

I am not sure I understand what you are asking. If a circuit has a Vin coming from the Arduino, you will use an output pin on the Arduino. Is that what you are asking?

Bob

 

[Viktory2k1]

This is all I have to go by. Yes but the power source doesnt go through the arduino, maybe just the ground? I have no idea. I may be better off just buying a power supply for these led strips, especially since I dont really have any transistors for the breadboard but I know I looked up some of these numbers and google said thats some were transistors. Who knows, the cats like to play with them and maybe they are under my mess of notes. Thankyou