I bought a very cheap solar garden light for £1.00 today just so I could pull it apart - what I find inside the guts is a solar panel (seems to give about 1.2V) connected to an IC of some sort labelled YX801 - this is connected to a 1.2 V rechargable battery and an LED as below
I can't find a data sheet for this and the only article I've found is in German and doesn't translate well.
It has 4 pins -
Pin 1 attached to the solar panel +ve
Pin 2 attached to the solar panel -ve
Pin 3 attached to battery -ve and one leg of the LED
Pin 4 attahed to battery +ve via the other leg of the LED and a resistor.
Clearly when Pin 1 and 2 are low (ie not charging), Pin 3 and 4 allow current to flow through the LED - but is that all it's doing ?
I'd like to know more about what this little chap is doing - is it moderating the voltage ? acting as a switch ? if anyone has come across this little chap I'd like to know as I intend to buy as few for cannibalisation.