led drive made from discreet components ?

[mark krawczuk]

hi, i want to make a led torch , something simple , that runs of 2 , maybe
4 , 1.5 volt battteries .
and to power 2 or 4 white leds.

is there a driver to make bit more efficent use of battery and leds ?
something that uses transistors etc , NOT ic`s.

thanks,
mark k

 

[Fun Tyme]

mark krawczuk wrote:

hi, i want to make a led torch , something simple , that runs of 2 , maybe
4 , 1.5 volt battteries .
and to power 2 or 4 white leds.

is there a driver to make bit more efficent use of battery and leds ?
something that uses transistors etc , NOT ic`s.

thanks,
mark k

Have a look at the range of LEDs and driver boards at Dealextreme.com,
you might get some ideas, but you may find pre-built stuff cheaper and
easier than making something yourself. LEDs really only need resistor
current limiting which often turns out more efficient than PWM.

 

[Phil Allison]

"mark krawczuk"


** A wise designer always specifies components that can be trusted to be "
discreet " .

Imprudent or exuberant types will never do.




....... Phil

 

[MisterE]

"mark krawczuk" <krawczuk@adam.com.au> wrote in message
news:FvGdna6VNpL5ywDanZ2dnUVZ_j6dnZ2d@adnap.net.au...

hi, i want to make a led torch , something simple , that runs of 2 ,
maybe 4 , 1.5 volt battteries .
and to power 2 or 4 white leds.

is there a driver to make bit more efficent use of battery and leds ?
something that uses transistors etc , NOT ic`s.

Efficent with transistors not in IC's ? ha ha ha har good one.
You can get dc-dc converts that will be over 95% but they are IC.