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voltage doubler

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Ralph Mowery

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Oct 8, 2018, 11:17:53 AM10/8/18
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I am building a simple full wave voltage doubler to power some external
circuits . I also want to use it at half voltage for lower voltage
circuits.

I am thinking that in this circuit I could take an output across just
one of the capacitors as it seems to be a halfwave circuit with added
components. Will this work or do need to put in a switch to switch out
the other capacitor and or rectifier?




https://www.daenotes.com/sites/default/files/article-images/full-wave-
voltage-doubler.png

Phil Allison

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Oct 8, 2018, 7:34:58 PM10/8/18
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Ralph Mowery wrote:
>
>
> I am building a simple full wave voltage doubler to power some external
> circuits . I also want to use it at half voltage for lower voltage
> circuits.
>
> I am thinking that in this circuit I could take an output across just
> one of the capacitors as it seems to be a halfwave circuit with added
> components. Will this work


** Yep.

Symmetrical loading is not required.


..... Phil

jurb...@gmail.com

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Oct 8, 2018, 7:49:20 PM10/8/18
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About the easiest way to do it is thus -

Version 4
SHEET 1 880 680
WIRE 352 64 208 64
WIRE 608 64 352 64
WIRE 688 64 608 64
WIRE 208 96 208 64
WIRE 352 96 352 64
WIRE 608 96 608 64
WIRE 208 176 208 160
WIRE 208 176 -16 176
WIRE 208 208 208 176
WIRE 352 208 352 160
WIRE 416 208 352 208
WIRE 560 208 496 208
WIRE 32 240 -16 240
WIRE 32 304 32 240
WIRE 416 304 416 208
WIRE 416 304 32 304
WIRE 208 320 208 272
WIRE 352 320 352 272
WIRE 352 320 208 320
WIRE 560 320 560 272
WIRE 560 320 352 320
WIRE 608 320 608 160
WIRE 608 320 560 320
WIRE 688 320 608 320
SYMBOL diode 224 272 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMBOL diode 368 272 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D2
SYMBOL diode 368 160 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D3
SYMBOL diode 224 160 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D4
SYMBOL sw 512 208 R90
SYMATTR InstName S1
SYMBOL cap 544 208 R0
SYMATTR InstName C1
SYMBOL cap 592 96 R0
SYMATTR InstName C2
TEXT -128 208 Left 2 ;AC input
TEXT 680 192 Left 2 ;DC output
TEXT 368 136 Left 2 ;closed for doubler
TEXT 40 288 Left 2 ;neutral
TEXT 40 152 Left 2 ;hot

Only 2 caps and 4 diodes.

Phil Allison

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Oct 8, 2018, 10:02:36 PM10/8/18
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Phil Allison wrote:
> Ralph Mowery wrote:
> >
> >
> > I am building a simple full wave voltage doubler to power some external
> > circuits . I also want to use it at half voltage for lower voltage
> > circuits.
> >
> > I am thinking that in this circuit I could take an output across just
> > one of the capacitors as it seems to be a halfwave circuit with added
> > components. Will this work
>

https://www.daenotes.com/sites/default/files/article-images/full-wave-voltage-doubler.png


> ** Yep.
>
> Symmetrical loading is not required.
>

** However, transformers have limited ability to supply current into a half wave load - in some cases only 10% of the rated current before unacceptable core magnetisation offset occurs.

The primary current soon becomes large & very asymmetrical, accompanied by a growling noise and overheating.


.... Phil

.... Phil




Ralph Mowery

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Oct 8, 2018, 11:14:12 PM10/8/18
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In article <e4a3d6d1-78d8-4740...@googlegroups.com>,
jurb...@gmail.com says...
>
> About the easiest way to do it is thus -
>
> Version 4
> SHEET 1 880 680
> WIRE 352 64 208 64
> WIRE 608 64 352 64
> WIRE 688 64 608 64
> WI
>

What is the program that uses this format ?

jurb...@gmail.com

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Oct 9, 2018, 1:09:11 AM10/9/18
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>"What is the program that uses this format ? "

LTSpice 4

There is a newer version but hardly anyone has it, I don't remember why. You might need the newer version on a 64 bit OS.

Ralph Mowery

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Oct 10, 2018, 4:07:36 PM10/10/18
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In article <5f9f45b3-eb8e-4a7a...@googlegroups.com>,
jurb...@gmail.com says...
>
> >"What is the program that uses this format ? "
>
> LTSpice 4
>
> There is a newer version but hardly anyone has it, I don't remember why. You might need the newer version on a 64 bit OS.
>
>

I have played just a little with ltspice in the past. How do I get the
text into the program ? When I just copied wat you sent into a txt file
and pasted it in, that is all that shows up on the screen, not a
schematic.

I did not have it on this computer, so I downloaded the latest version
for win 10.




jurb...@gmail.com

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Oct 10, 2018, 5:28:38 PM10/10/18
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OK, you get the beginning where it says "Version", you take the mouse and drag from the beginning there and move the mouse down. You then get to the bottom. you can tell the commands so you know where they end. Where I wrote "Only two caps and four diodes is NOT part of the text you want.

With all that blued up, or whatever color your scheme makes selected text you hit Ctrl+C, or rigthclick and click "Copy" form the box.

Now minimise the browser and whatever, get to the desktop, (or folder somewhere) and either from the menu or right click hit "New and then go to "Text Document". Click that and and let it open. With a left click put the cursor in there and either hit Ctrl+V or rigthclick and hit paste from that box.

It should all appear. Save. You can hit close and it'll ask to save, say yes. Now go to the file and remname it, but you need to change the extension as well, so I don't know how much trouble newer Windows will give you but you rename it to "Whatever.asc". then double click it and it should open up LTSpice and show the schematic. Once you get handy with the program you can run simulations on it, after choosing the circuit values of course. It can figure out like ripple on that doubler and you can change the cap values and a few other parameters, and for the current draw you need to add a resistor and specify its value with Ohm's law. Like if you are in the US and in doubler mode and want to see how it performs at 1 amp draw, put a 320 ohm resistor there because it is 320 volts. You DO have to figure out some things, especially component values, it does not have that ability.

Giver it a try and come back with any questions. I am surprised it isn't in the manual actually, it is the modus de jure to put a schematic through a text only medium, such as this newsgroup.

The only main problem with it is that it doesn't have a god damn potentiometer. There is a way to make one, but I am not good enough with it yet. I wish there was a place i could just download it and pout it in the "library" but have not found it. The other problem is that the recipient of the file has to have the symbols all in his library. If not it will display all it can without whatever it doesn't recognize. That's why I would like to see a pot downloadable, so it is standardized. If five people do it five different ways it is not going to work.

If you got a pot in your library we'll have to figure out how to propagate it. Hopefully it'll work in 4.

Yeah right, hopefully, famous last words of the damned. LOL

jurb...@gmail.com

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Oct 10, 2018, 5:31:15 PM10/10/18
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And no bitching about me mixing Latin and French, it's all Greek to me.

Ralph Mowery

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Oct 10, 2018, 7:39:59 PM10/10/18
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In article <1bbb09aa-eb01-4524...@googlegroups.com>,
jurb...@gmail.com says...
>
> It should all appear. Save. You can hit close and it'll ask to save, say yes. Now go to the file and remname it, but you need to change the extension as well, so I don't know how much trouble newer Windows will give you but you rename it to "Whatever.asc". then double click it and it should open up LTSpice and show the
schematic. Once you get handy with the program you can run simulations on it, after choosing the circuit values of course. It can figure out like ripple on that doubler and you can change the cap values and a few other parameters, and for the current draw you need to add a resistor and specify its value with Ohm's law. Like if you
are in the US and in doubler mode and want to see how it performs at 1 amp draw, put a 320 ohm resistor there because it is 320 volts. You DO have to figure out some things, especially component values, it does not have that ability.
>
>

Thanks, just changing the text file to .asc was the trick.

I had done the copy and past into notepad but it saved it as a
circuit.txt Had I saved it as circuit.asc I would have had it.

It has been a year or two from the last time I looked at LTSpice.



jurb...@gmail.com

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Oct 23, 2018, 2:29:56 AM10/23/18
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Actually I did that kinda wrong. It is not bad per se, but the right way is -

Version 4
SHEET 1 880 680
WIRE 352 64 208 64
WIRE 608 64 352 64
WIRE 688 64 608 64
WIRE 208 96 208 64
WIRE 352 96 352 64
WIRE 608 96 608 64
WIRE 208 176 208 160
WIRE 208 176 -16 176
WIRE 208 208 208 176
WIRE 352 208 352 160
WIRE 416 208 352 208
WIRE 608 208 496 208
WIRE 608 208 608 160
WIRE 32 240 -16 240
WIRE 608 256 608 208
WIRE 32 304 32 240
WIRE 416 304 416 208
WIRE 416 304 32 304
WIRE 208 320 208 272
WIRE 352 320 352 272
WIRE 352 320 208 320
WIRE 608 320 352 320
WIRE 688 320 608 320
WIRE 0 0 0 0
SYMBOL diode 224 272 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMBOL diode 368 272 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D2
SYMBOL diode 368 160 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D3
SYMBOL diode 224 160 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D4
SYMBOL sw 512 208 R90
SYMATTR InstName S1
SYMBOL cap 592 96 R0
SYMATTR InstName C2
SYMBOL cap 592 256 R0
SYMATTR InstName C1

tabb...@gmail.com

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Oct 24, 2018, 10:36:09 PM10/24/18
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Spice did have a pot originally, but they found people couldn't reach it through the glass screen. :)

2 fets & a ramped etc voltage to the gates?


NT

peterw...@gmail.com

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Oct 29, 2018, 1:34:13 PM10/29/18
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To elaborate just a bit on Phil's correct answer:

Hot to hot = doubled voltage.
Hot-to-ground = half-voltage.

https://img.bhs4.com/e7/1/e71df333b176823b913fdddc802d6fc749bce9a5_large.jpg

One side will be - to ground +.
One side will be + to ground -.

To see this in action - exactly this - look at the filament voltage schematic for a Dynaco PAS. As these are all dumb components, loading does not change anything - to the capacity of the source in any case.

Peter Wieck
Melrose Park, PA
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