Russian voltage multiplicator stacking

[nix85]

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[nix85]

At another forum they think V terminal might be for some negative bias and that it would be tapped between V and ground with a cap inbetween not to short the input on negative halfcycle. No one knows for sure and i guess it doesn't really matter.

Another question emerged from this, when i asked them isn't that cap between V and ground shorting the input on negative halfcycle this guy answered that cap once charged no longer conducts. I said, yea, but that is clearly not correct, all these caps charge up and stay charged and yet they do conduct. To this they have remained silent.

https://www.youtube.com/watch?v=litsAzP4oqw

[Thaelin]

Standard rule there: a capacitor will block DC and pass AC.

[nix85]

Standard rule there: a capacitor will block DC and pass AC.

Yes, that is a general rule, but obviously it's not that simple.

We all know cap is like open circuit for DC and low frequencies according to XC= -1/2πfC, higher the frequency lesser the reactance just like the opposite is true for an inductor XL= 2πfL.

If we feed it AC of higher frequency it is like closed circuit, no mystery here, it charges and discharges on each halfcycle, displacement current passing through it all the time.

Another case is when it's used to filter out the bias in class a and b amps. So we feed it pulsed DC and yet only the AC component passes through. Interesting effect if you look into it, how does it "know" where to place the 0, input voltage can vary at various levels, for example from 1 to 3V or from 3 to 5V, yet the cap "knows" and places zero at +1.5V or 4V automatically.

And finally, the example of voltage multiplier. Let's see exactly what happens, when C1 charges to 12V, now source changes direction, if there was no other cap, C1 would now discharge and charge to 12V in other direction. All sweet and clear.

But since C2 is there, 12V from the source + 12V on the cap (now in same direction) charge C2 to 24V, and yet this does not discharge the C1 and charge it in other direction. I find this very strange.

EDIT: C1 DOES discharge when charging C2 to 24V. I was misinformed by youtube guy The Organic Chemistry Tutor. I knew how basic doubler works but i took his word for granted.

What happens is simple with this correction. When C1 and source charge C2 to 24V C1 is now discharged but on next (negative) halfcycle C1 is charged to 12V again. AT THE SAME TIME (in parallel) 12V from source + 24V on C2 charge C3 to 24V (36V - 12V on C1). This discharges C2 but on next (positive) halfcycle it gets charged to 24V again and at the same time 12V from source + 12V on C1 + 24V on C3 charge C4 also to 24V (48V-24V). And so on in same manner.