About

This page contains a single entry from the blog posted on October 13, 2010 8:53 AM.

The previous post in this blog was Crafting cool cardboard cameras.

The next post in this blog is Eyeballing for donations with Arduino.

Many more can be found on the main index page or by looking through the archives.

Sponsored by RS

Sponsored by RS This blog is brought to you in association with DesignSpark, powered by RS.

Subscribe


Sign up for the fortnightly Gadget Master eNewsletter. Get design ideas and circuit schematics straight to your email inbox, no fuss. Just tick the option for Circuits.


RSS Subscribe to this blog's feed
[What is this?]
ElectronicsNews on Twitter Follow ElectronicsNews

Archives

Recent Comments

Alun Williams - Electronics Weekly.com on LED Wizard calculates resistors and draws schematics: Thanks for the feedback, Paul. What do other readers th

Peter F Vaughan on LED Wizard calculates resistors and draws schematics: Well, I tried this LED wizard to drive 7 LED's from a 1

Sponsored by...

Sponsored by RS This blog is brought to you in association with RS.

« Crafting cool cardboard cameras | Main | Eyeballing for donations with Arduino »

LED Wizard calculates resistors and draws schematics

LED Wizard.jpgHere is an excellent resource, certainly worth bookmarking if you are creating your own LED lighting systems - the LED series/parallel array wizard.

It describes itself:
The LED series/parallel array wizard is a calculator that will help you design large arrays of LEDs. The LED calculator was great for single LEDs--but when you have several, the wizard will help you arrange them in a series or combined series/parallel configuration. The wizard determines the current limiting resistor value for each portion of the array and calculates power consumed. All you need to know are the specs of your LEDs and how many you'd like to use.
Check out the screen grab below for our example generation.

As you can see there are also "compilation warnings", advising points of concern about a design.

Does anyone know of other LED calculation resource pages? Please get in touch and share with fellow Gadget Masters.

LED wizard full.jpg






TrackBack

TrackBack URL for this entry:
http://www.electronicsweekly.com/cgi-bin/mt/mt-tb.cgi/174907

Comments (2)

Peter F Vaughan:

Well, I tried this LED wizard to drive 7 LED's from a 13.5V source (LED voltage drop = 2.7V each), at 20mA per LED.

One of the options it gave me was 5 LED's in series, with a 1ohm limiting resistor, all paralleled with the last 2 LED's in series, with 470 ohms.

Clearly, the 2-LED-plus-470-ohms chain is fine. But I'm really worried about the 5-LED-plus-1-ohm. (Where the 1 ohm came from beats me as the 5 LEDs add up to 13.5V anyway). If the 13.5V rose to 13.6V then the current would rise massively! And if LED voltage drop altered, due to temperature etc, then again this chain's current would alter drastically. No warnings are given.

Not a credible wizard I'm afraid...

Thanks for the feedback, Paul. What do other readers think of its results?

Post a comment

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)