White LED from 2.4v Nicad from Solar Panel

 I have a solar powered torch, large case, which has a 2.4v nicad
battery.

In order to increase battery life (30 mins on torch) I wish to swap
ordinary 2.4 bulb with 3.3v white led(s)

Is there a simple way to do this, ie 2.4v to 3.3 step up circuit

TIA

  Solar powered torch? That possibly a lantern or flashlight? ;)
Have you tried hooking the LED's up to the 2.4v batteries to see what would
happen? I do remember 'em working very well even with batteries that were
'run down' quite a bit past the 'voltage point' that they were rated at, but
I sure can't remember at what point they did become useless..

 

Doesn't work, 3,3v leds !!!

 Duh..  I read it backwards.. ;)

 On Sat, 19 Feb 2005 03:46:17 GMT, LEDMan@3v.invalid (LED Man)
wrote:


There are circuit designs on the Internet but I would suggest that
the simplest and cheapest way is to buy a now common Chinese made
multi LED torch and just wire it in or remove the little
electronics pc inverter board.      They work very well.
Building your own inverter requires some electronics knowledge and
parts like inductors, capacitors  and ICs/transistors.

One nice little US $10  machined aluminum cased flash I recently
bought off a street vendor, runs off only one AA and worked down
to an amazing 0,8V -- giving there about a 5ma LED current.
Enough light to look for keys or read a map etc.   There are many
multi LED torches oen could easily adapt..

The effciency of LEDs is roughly the same as incandescents nowdays
but since LEDs put out light at much lower currents their usable
battery voltage can be very wide and thus make for very efficient
battery use with or without an inverter.   Alternatively,
yellow-orange LEDs work very well right off two NiCads with just a
simple ballast resistor and can give a nice "warm" light.

  .