led’s 12v in parallel

Printed From: the12volt.com
Forum Name: Motorcycle Electronics
Forum Discription: Installing Stereos, Alarms, Remote Starters, Lights, Garage Door Openers and other electronics on motorcycles.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=99670
Printed Date: May 06, 2025 at 4:30 AM

Topic: led’s 12v in parallel

Posted By: ltkenbo
Subject: led’s 12v in parallel
Date Posted: December 05, 2007 at 12:56 AM

Hey, new here and I had a question about wiring some LED's to a 12v source. Me and my friend are designing a brake light for his motorcycle.

Anyways, my main question was if I can wire them in parallel like the following diagram using a single resistor. I ohms law with the equation (V1-V2)/I * N

V1=Supply (12v)
V2=Volts for an individual LED (3.5v)
I=Current for an individual LED (.020a)
N=Number of LEDs in parallel circuit (12)

Is this diagram and equation correct. Would this setup work hooking up to a 12v battery on a motorcycle.

posted_image

Thanks :-)

Replies:

Posted By: techman93
Date Posted: December 05, 2007 at 1:07 AM

four rows of three led's with 820 ohms resistance on each row attached to negative side.

https://led.linear1.org/led.wiz

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The wire I'm test'n isn't doin' what it's supposed to be doin'... I am so glad I printed that tech sheet, with the wrong info.
Do it right the first time... or I might have to fix it for ya

Posted By: ltkenbo
Date Posted: December 09, 2007 at 5:38 PM

My question though is would this work. This website: https://www.quickar.com/noqbestledcalc.htm
shows the same schematic I came up with and so does this one:
https://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator

Would this setup work??