# Multiplying a DC voltage without a transformer?

Discussion in 'General Electronics Chat' started by electronice123, Nov 28, 2009.

1. ### electronice123 Thread Starter Active Member

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I know an AC voltage can be multiplied and converted to a high dc voltage using a voltage multiplier.

Is there any way to multiply a DC or pulsed DC voltage to say 20kV without the use of a transformer???

2. ### SgtWookie Expert

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Going from a low voltage to 20kv wouldn't really be practical without the use of a transformer.

You could use switched capacitor networks to boost DC, but it certainly would take a while, and you'd lose power in the switching/charging/etc.

3. ### electronice123 Thread Starter Active Member

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OK. I was just wondering because I have never seen or heard of any other way than by using a transformer. Seems to me it would be just as easy to use a small inverter and voltage multiplier, or a transformer like you mentioned.

Thanks!

4. ### SgtWookie Expert

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Well, you can use switched inductors in a boost configuration to go up maybe 20x or so your input voltage pretty easily. But if you want to go from 12v to 20kv, that's really a different ballgame.

5. ### Wendy Moderator

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And you can use a diode multiplier for lower increases, like X2 or X3. It requires a switching oscillator though, but that is an easy option nowadays.

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7. ### GAMAL YONES New Member

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dear friends

how can i calculate the value of capacitance and capacity of diode which use for voltage doubler

many thanks
gamal yones

8. ### Bychon Member

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LOL! The Van De Graff generator is a perfectly reasonable answer, considering nobody said how much current was needed. Thanks. Your imagination struck me as funny and I appreciate a laugh.