Hey everyone,

I wondered if someone could point me in the right direction. I have a sinusoidal source of 200mV pk-pk which can supply a current of 30uA pk-pk. I would like to passively rectify this to a DC voltage for accumulating in a capacitor but I'm not sure how to decide on the correct schottky diodes to use.

Any advice would be awesome.
Cheers!

 

I have realised, this may not be possible, so I would like to use mosfets to rectify and I will control them with secondary circuitry. However, how do I go about choosing some suitable ones, there are millions!

Cheers

 

You asked almost the same question here http://forum.allaboutcircuits.com/showthread.php?t=32740. And I think the same answers will apply here to

 

previously it was stated: "this is not usable power. discrete silicon components require microamps at best."

I was talking about nA then, I am now talking about uA. Since uA are in the operating range of discrete silicon components, I thought someone may be able to help me.

 

Power is power. .2 volts and .00003 amps is .000006 watts. It is hard to imagine the utility of such a low amount of power. What is your ultimate application?

 

I believe that this is not possible using a passive approach. The Vf of a Schottky diode is in the range of 0.2 to 0.3 Volts. A precision rectifier based on an operational amplifier working from a battery or power supply is the only chance. If this is not possible or practical then I fear that you will be unable to accomplish your goal. Sorry!

 

If you are going to use outside circuitry, you will need outside power. Can you not use that? What, besides charging a capacitor, is the ultimate goal?

 

Try a "cat's-whisker detector". They appearently have almost no forward voltage drop and work at very low power. i.e. radio signal detection many decades ago.

Google it. You have to make one.

Good Luck