Comments on: LED Boost Circuit – Joule Thief

By: ben

ben — Fri, 27 Nov 2009 22:54:44 +0000

Is the voltage boost proportional to the light output decrease? Im wondering if the LED output is less (in mcd or lumens) than if you ran the LED at its typical 3-3.5Vf.
Anyone? Thanks.

By: Fred

Fred — Fri, 20 Nov 2009 02:33:08 +0000

i found that http://www.thejoulethief.com sells these kits as well

By: mehadi

mehadi — Thu, 05 Nov 2009 03:18:53 +0000

what are the component needed to make this device

By: grant t

grant t — Fri, 18 Sep 2009 23:05:43 +0000

hey this is a great idea. What is the output voltage from 2 aa size batteries. In trying to power 9 10mm leds using 21/23 (12v) batteries. Also what is the layout for your circuit. It looks like i can get these parts from disposable cameras . If not then could i get a list of parts and a design layout and i can try to make one. Thanks

By: clint

clint — Fri, 17 Jul 2009 17:15:28 +0000

will it destroy the batteries

By: clint

clint — Fri, 17 Jul 2009 17:12:38 +0000

could i use the joule thief to power 3 leds from two aa bateries, which inturn will be charge by a solar panel 0.25 W 2.5 volt
thanx

By: dog812

dog812 — Sat, 28 Feb 2009 05:31:57 +0000

I need a joule thief to power 21 RGB LED’s from a single AA battery.. is this possible? How long will they last?

By: Raffaello

Raffaello — Tue, 24 Feb 2009 14:05:19 +0000

How to make a simple light switch from this circuit: connect a photoresistor between the base of the second npn (the one driving the coil) and ground, and the led will light with darkness and go off on daytime. If you want, put a 47k pot in series with the photoresistor to adjust sensitivity.
It works!!

By: Neb

Neb — Sat, 26 Jan 2008 19:46:31 +0000

also the LED boost circuit diagram, send order info. thx.

By: Roy Tang

Roy Tang — Thu, 29 Nov 2007 04:24:07 +0000

I am interested to convert this into LED driver circuit for battery application to consume battery power. How can this be done?

I can be contacted at tang.chee.wai@rigel.com.sg