Boost photodiode output voltage with transformer?

[icypenguenz]

For the design of a no-power light detector, I need to boost the output of a small photodiode array (produces 20mV @ 1uA) to 1.5V. Since a short voltage spike would be sufficient and the light source will be oscillating, shouldn't a transformer be able to do the job? I tried this with a 1:50 turn ratio transformer but didn't observe any additional output at the secondary.

Any help would be greatly appriciated, thanks!

 

[Sceadwian]

You forget the basic principals of transformers. That voltage comes at the cost of current. So for 50 times the voltage, you're getting 1/50th the current, which is 20nA That's hardly a useable amount of power. You could rectify the output signal with a schotky rectifier, and charge a capacitor, but at that charge current it could take some time.

 

[crutschow]

It's rather difficult to boost the voltage of such a low power signal (20nW) without a powered amplifier.

What are you going to do with the signal output?

 

[MrAl]

Hi,

String 75 of them in series.

 

[Sceadwian]

The solar cell from a pocket calculator might be more useful, makes more sense anyways as if your light source is bright enough to detect it will also provide you enough electricity for doing something.