Help Powering 45 LEDs (3.2v whites, Blues and 2v reds)

[gcadman]

Hello All,

I have been reading and hunting for a means of runnig 45 leds in parrallel and I am very interested in the JT circuit.
I have a few questions for you guys:

- Can this be done on 1 or 2 circuits?
- Do I need to scavange a Fuji Camera Circuit?
- Is there a particular circuit that is bes suited to this, I saw that video on 200 leds and it brought me here
-  What voltage will i need (1.5v 12v)?
- Will each Led need a resistor to limit current ?

Answers to some application questions
- Leds are 10mm White(3.2v), 10mm Blue(3.2v), 10mm Red (2v)
- If i ran them all at 20ma the mA would 900ma 
- I would need alot of capacity

What I am looking for is a long runtime on 4 to 8 batteries (AA)

Thanks for any help and education.
- Gary

[gcadman]

As I tink of it, I kinda understand the idea of the circuit.

I would like to run the sysem off 1.5v (4 D's in parrallel 48,000 mAh)
that way I could run my 44 leds at @18ma =880mA draw for @50+hr

I have been studying all the circuits and still havent figured out how many leds I can run off one circuit
Do i just need a boost circuit that will give me 5v and add a resistor to each LED?

I have  30 whites(3.2), 6 blues(3.2) and 8 reds(2v)

- Thanks for any help
Gary

[fritznien]

would it not be easier and cheaper to run the leds off D cell batteries in series to get the required voltage.
also batteries in parallel can cause problems when charges are unequal.

[gcadman]

Yes,  I was trying to get as much capacity as can and hoping to use a jt circuit to help
My problem is the LEDs will draw @900 mA. On 12000mah they would run @ 12 hrs

The only other way is to wire the less in series to lower the draw

Am I off base?   Any suggestions?

-thanks

[fritznien]

your missing a few things, the leds draw 20ma at 3.2 and 2 volts but a d cell only puts out 1.5
so your numbers are a bit off, more power must be pulled from the bateries to light the leds to full brightness.
the JT would run them all in series but it would require more power to do so because of loses.
also your talking about a fairly heavy duty one that may take you a few trys to get right.
4 d cells will give you 6 volts use that instead of 5.
then all that is required are currant limiting resisters.
quick cheap reliable and no high voltage to play with.
can you run 2 blues in series off 6 volts?
how about 3 reds?