I am looking for a circuit topology to be used as a micro power energy harvesting battery charger.
Here are the requirements:
An input impedance that is fairly constant in the 500 to 1000 ohm range;
The output would be a near constant voltage in the 1 to 5 volt range;
The output current would be rough proportional to the square of the input current.
The power handling ability to be in the 10 to 200 milliwatt range.
I am thinking of using a SMPS with some sort of nonlinear feedback element to make the output current roughly the square of the input current.
Is this possible?