Beginner LED project tutorial

[stage3-S4]

Yes, they are wired in series and you are right that for this project a parallel circuit would work better. For a large project though, where you would have multiple strings, parallel circuits are not ideal. From what I was told, if you connect a few parallel strings together on a driver (a larger driver than used here, like a meanwell type driver) and one LED fails, it will overdrive the other string and probably fry all of the LEDs on the other string. I'm just an amateur at this and really don't know everything, I'm just following what I've read.

Wiring the leds in parallel with each other would put 15 volts across each LED which is not ideal considering they are run at a max of 3.75 volts. Also the current would not be enough as you would need way more than 1amp. Just remeber that in a parallel circuit that voltage always stays the same and current changes, and in a seires circuit the current is always the same and the voltage changes.

You would not want to be put more than 1 string of leds on single driver, as you do run the risk of overdriving the other leds, as you mentioned.

 

[azazel]

Thats true, but it is possible to drive more than one string of leds from one driver. The only one you must to do is - increase the current. For example

This "bucpuck" is set to 350mA:

and this one is set to 700mA

Both circuits are the same - based on MBI6550 chip.

 

[Chiefmcfuz]

Ok now I am lost.

Does anyone have a step by step Solder here, glue there, wire here diagram for us electrically challenged people?

 

[azazel]

Diagram ? - no problem, just tell how much led's You want to use - I can draw it, but not today There is 00:08 AM in Poland so I must tell "goodnight "

 

[Chiefmcfuz]

Whatever you want to draw just make sure it is written in Electrical For Dummies so I can understand it.

 

[stage3-S4]

Thats true, but it is possible to drive more than one string of leds from one driver. The only one you must to do is - increase the current. For example

This "bucpuck" is set to 350mA:



and this one is set to 700mA



Both circuits are the same - based on MBI6550 chip.

yes, thats what I was saying, i just misunderstood the op when he mentioned putting the leds in paralell. It seemed as though he wanted to put each led in paralell with the source voltage so each would be receiving a full 15 volts. You are correct that if you want to run another bank of leds from the same driver,you would have to make sure that you provide enough current to power up the extra set.

 

[bruma bull]

oops did i start this?

 

[noodleman]

is there a write up to power 1 of these bright LED's off a battery pack with a dimming option?

 

[azazel]

is there a write up to power 1 of these bright LED's off a battery pack with a dimming option?

Do you thing about flashlight with powerled ? There is many solutions depending from battery voltage - from "step-up" converters when battery voltage is below "Led Voltage", to "Buck" when battery or power supply voltage is much higher than leds needed.

Here is the most simply "step-up" circuit (As I remember) - http://www.elektroda.pl/rtvforum/download.php?id=6938

About dimming - MBI6550 has an DIM pin input. Connecting to this any PWM signal source - based on uProcessor or NE555 chip - brightness of led can be changed. Datasheet shows how to do it - thats better way due to my poor english...

BTW - I've got many PM - you asking me to show as simply as possible the way to power leds. I'am afraid that I can't do this (I mean simply) without translator

 

[fallenlordz]

great write up - very easy to follow for me - thanks!
:iamwithst

 

[coralcrazy]

WOW....Great post