ee

what you'd need is smps step down design however this network requires a control ic (most do these days) do a search with the following keywords:smps stepdown circuit or smps stepdown application notes,-- most semiconductor manufacturers will have this information on their websites

you could make a simple one with a rectifier and resistor(s)

audioguru: Hi Bryen, Welcome to our forum. I've tried it. A LED makes a very inefficient photodetector. With an extremely bright light up close or light from a similar LED up close, they produce a little more than 1 volt with hardly any current. They also conduct hardly any current. Why not use an efficient photo-transistor or photo-cell, that's what they are designed for. ------------------------------------ to overcome the insensitivity you could use a high-speed opamp on the other hand yes youre right why not use what youvemention or infrared reciever,transmitter leds costing no more than a regular led