Solar Powered IR LED Flasher Circuit Request

I need a circuit that will flash a standard IR LED.

I do not want it to include a 555 IC or any other such digital control. This needs to be analog.

I plan for it to run off of a solar cell(the one i have provides power at .5V and 1.5mA) with a rechargeable battery as a storage bank. I know this is extremely low voltage/current for a recharging system, but if you have a solution by all means include it.

Blinking rate is not that important, although options for changing the rate would be appreciated. It should not blink slower than once/sec tho.

I hope someone knows enough to be able to pull this off, my expertise is in programming not EE.


Goodhart6 years ago
if you could convert the output of the solar cell(s) to AC, a couple of small capacitors would be all you needed for blinking, but then, you'd have to deal with running AC though the LED or convert it back. It MAY be possible to use a resister and capacitor to combo to prevent the current from flowing until the capacitor is charged to the point that it overcomes the bias and discharges through the LED.
jeff-o6 years ago
All I can think of trying is to use a standard solar LED garden light, and modifying the circuit so that the flash rate is reduced. These typically blink the LED at tens to hundreds of thousands of hertz - what frequency range are you aiming for?
qs6 years ago
With a .5v supply, its not enough to bias a silicon transistor on. Old-time germanium has a lower operating voltage but will not have the amplification to do what you suggest.

Add another cell to get 1v and it becomes straight-forward.