AC - DC rectification

kubeek said:

No exactly the opposite. Any active ciruitry such as switching regulator needs about a thousand times more power to operate than what you have available. You need a completely passive solution with as little leakage as possible. Stick with a single low leakage diode as a rectifier, and a second zener diode to clamp the voltage. Fedd the result into a very low leakage capacitor.

I have no idea what are you trying to power, but I dont think your source will be able to power anything. Can you give more details about what is that mysterious power source and what you are trying to do with it?

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Source is a Vibrational based Energy harvester . and my load will some kind of sensor ( not sure ).

4pyros said:

Ok now I am really confused.
Where is the 14 volts AC coming from?
What are you trying to power wit 3 volts DC/

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Source is a Vibrational based Energy harvester . and my load will some kind of sensor ( not sure ).

4pyros said:

Ok now I am really confused.
Where is the 14 volts AC coming from?
What are you trying to power wit 3 volts DC/

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That's why I don't get involved with these threads..
I am borderline nutty as it is. This kind of stuff does not help...

Just thought I should say that.

Regards,
tvtech

surjit said:

and my load will some kind of sensor ( not sure )

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Then how do you know you need 3 volts?

surjit said:

Source is a Vibrational based Energy harvester . and my load will some kind of sensor ( not sure ).

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What the bleep is that?
and how do you know you will get 14 volts AC out of it?

Like this?
https://www.nipslab.org/files/file/...tone Introduction to vibration harvesting.pdf

Energy harvesting is getting nothing from nothing.
Remember "shake-to-charge flashlights" a few years ago? You shake it until your arm is ready to fall off then it lights dimly for a few minutes.
I got some for free from seminars but I have never used them. I also have some wind-up flashlights that I never use.

My son gave me a cheap Chinese 24 white LEDs flashlight. I threw away its leaking low power carbon-zinc AA cell and use a rechargeable Ni-MH cell. I use this flashlight often.

I have seven LED chasers that I made. They operate for months from 2 or 4 AA alkaline cells. They are bright.
Disposable batteries are cheap, available everywhere and produce lots of power for a fairly long time.

audioguru said:

Energy harvesting is getting nothing from nothing.

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Like over unity?

surjit said:

Source is a Vibrational based Energy harvester . and my load will some kind of sensor ( not sure ).

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I think this is what the OP wants, given the above post (although getting one might be problematic):
http://cds.linear.com/docs/en/datasheet/35881fb.pdf
Variable Vin(s) and Vout(s) and extremely low Iin (tens of uAs, although not nAs).

I've used similar LT devices (mV, low I AC inputs from miniature Savonius rotor generators) and they work very well. Note the VGood pin.