# Need help with voltage doubler

Discussion in 'Electronic Basics' started by [email protected], Nov 11, 2005.

1. ### Guest

I keep blowing capacitors so I need help Right now the only two
good capacitors I have are 50v 1000uf and 50v 47uf.

right now DC source 5.25 volts

Isn't it

possitive on battery, capacitor #1, diode going to each leg of the 2nd
capacitor, one leg of 2nd capacitor going to ground, the other going to
negative on the battery.

2. ### Andrew HolmeGuest

Get the right capacitors. You want two of equal value.

Electrolytic capacitors are sensitive to polarity and will blow up if you
connect them the wrong way round; subject them to excessive AC current; or
exceed the rated voltage.

The first hit on Google for "voltage doubler" is a simple DC-DC converter
using a 555 timer.
The second hit shows the classic voltage doubler circuit using an AC mains
transformer.

http://www.reconnsworld.com/power_voltdoubler.html
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/voldoub.html

The + sign against the secondary of the transformer in the 2nd link makes no
sense.

3. ### Vanheesbeke StefaanGuest

Voltage double on a battery with only some caps and diodes??? I think you
need some switching or an AC source.

4. ### petrus bitbyterGuest

It isn't. Can't but strongly advise you to find a textbook covering basic
electricity, voltage, current, power, Ohms and Kirchhoffs laws, DC and AC.
Don't expect someone to build an electronic circuit without at least this
basic knowledge.

petrus bitbyter

5. ### Guest

It does seem to work with a coil/magnet setup that outputs about .6v
AC. I've seen over 2v off of that. Right now I'm thinking regulated
1000v 25ma power supply thats already doing everything for me

Eric

6. ### Guest

The second link looks like what I'm trying. What about "non polar"
electrolytic capacitors?