Joule Thief

[Groundloop]

@powercat,

I'll put that on my to do list.

Attached is my newest circuit. It is a mosfet version. The mosfet
is protected by 4 zener diodes. I get full light output in
my 12 Volt 1,8 Watt LED bulb with a input of 12,0 Volt and 0,06Amp (0,72W) current
when run from the circuit. The LED Bulb is using 0,08Amp @ 12,0 Volt (0,96W) when
connected directly to the PSU. The mosfet transistor runs cold, no waste power
in the circuit.

GL.

[Groundloop]

Hi,

Attached is my newest version of the ferrite resonant circuit.
I have added a couple of diodes to keep the transistor from
blowing up. I also has increased the turns of the output coil.
I have also found that I can "tune" the core resonant frequency
point by using a variable capacitor (10pF to 47pF) as shown.
The light output get a little brighter at some points of the frequency
scale when tuning the capacitor without the power input increasing.
This circuit runs cold without any heat in the transistor.
The circuit runs from a input of 1 to 3 Volt. My goal is to fine
tune this circuit to be run from 1,5 Volt. (One battery cell.)
The research will go on.......................................................

GL.

[xee2]

120 VAC LED bulb lit using 1.5 volt AAA battery.

video >>>>   http://youtu.be/EOqKv0awVv8

[Pirate88179]

Xee2:

Nice work.  Try using two of the bulbs.  I found that I can light two LOA 120 volts bulbs with an AA and the light of each is just about as bright as it is using only one bulb.  So, I got almost twice the light.  Leds are the way to go...much more light than I ever got from a tube or cfl.

Bill

[Groundloop]

Hi,

I have taken apart a 2 Watt 230VAC LED bulb. The bulb had 42 leds
on four circuit boards. 12 leds on three side boards and 6 leds on the top
board. At the bottom there was a circuit board with a LNK302 IC. The main
input did go through a safety resistor of 15 Ohm. Then there was a MB6S
diode bridge. The input was feed through a serial coil and two smoothing
electrolytic capacitors of 4,7uF 400 volt. The LNK302 IC was attached to
a EL817 opto coupler. This opto coupler was melted because I have used
this bulb on my Joule Thief, probably with too high input voltage. So if you
have used this types of bulbs on a Joule Thief circuit, then do NOT reuse
the led bulb on the mains. Attached is some images and also the data
sheet for the IC.

GL.