diodes

Kevin Weddle

Feb 23, 2004
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They always conduct. No matter what.

These two circuits are different. Resistors don't clamp a voltage. The voltages halve, halve, and halve again until Vp.

View attachment ac.pdf

 
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audioguru2

Apr 6, 2004
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The same current flows through parts that are in series so their sequence does not matter.

If your series circuits have the same parts values and the same AC input signal then their capacitors charge exactly the same.

Your circuits have no input signal so nothing gets halved. A diode rectifies, it does not halve. 

 

Hero999

Oct 28, 2007
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If an AC signal is applied to either of those circuits, the capacitor will just charge up, then no current will flow, except that due to the diode reverse leakage and capacitance.

 

Kevin Weddle

Feb 23, 2004
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I know there is a simpler 15V to 45V voltage multiplier than the one I posted. It might be adequate. I won't bother posting that one.

 

Kevin Weddle

Feb 23, 2004
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Something I noticed about voltage multipliers. I've never seen two equally charged capacitors reverse bias a diode. But as long as the capacitors are completely charged the diode is reverse biased.

 
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Kevin Weddle

Feb 23, 2004
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I think at 1Khz, the capacitor could not completely charge in one cycle.

No, that's not it. You have to make the resistance higher than the impedance of the capacitor. 

 
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