Current switch?

I have some solar panels that produce 3v at 175ma. I was wondering if i could somehow make a switch to have it turn on when the panels are producing at least 100ma. Maybe also a switch for 150ma too :)
Any ideas?? If additional voltage is needed it shouldn't be a problem :)
Thanks!


Use the voltage trigger to drive a separate transistor to switch the load - a Mosfet would be ideal, because it would become a perfect "blocking diode"  when its off, and a better switch than a diode when its on.
You can't, they only "produce" 175mA when they are connected to a load which can DRAW 175mA @3V.  Since voltage is proportional to light intensity, you'd do better switching on VOLTAGE.

Steve
astroboy907 (author)  steveastrouk7 years ago
the circuit i have when switched on will suck up any current produces by these (i think) when the ipod is plugged in. it is pretty much mintyboost (boosted) actually if it could trigger at 120 ma it would be better :)
Voltage triggers might work (nned to have it trigger at least at 1.8v) but do u know of any that would handle this much current (also if you could find one that triggers somewhere around 4.6 to 4.8 v that handles this much current it would be even more appreciated)
Thanks!