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Volage multiplier questions

  1. May 19, 2014 #1
    have a few questions about designing a voltage multiplier. lets say I want 1kv output from 9v battery source.
    - do all the caps have to be electrolytic caps?
    - how to choose what caps to use?
    - how to choose what diodes to use?
  2. jcsd
  3. May 19, 2014 #2

    as far as i know you can use any type of capacitor you want. the value might be different though.

    and you can also use small transformer to do this. first use a switching circuit consisting of transistor and caps to make it AC then feed it into a transformer of proper number of turns. the current will be really small but you should get around 1kv.
    Last edited by a moderator: May 27, 2014
  4. May 19, 2014 #3
    Thanks, I wasnt sure if electrolytic capacitors had to be used, because that is all I see people using. I would consider stepping up the voltage through a tranfromer before supplying voltage to the multiplier, but is what i dont know is voltage ratings for the diodes and capacitors. or does that even matter?
  5. May 23, 2014 #4
    that should matter, you can check datasheet of any product to find out its max ratings.
  6. May 24, 2014 #5


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    on the HV output side, you should be using disc ceramic capacitors with the appropriate HV ratings
    you are not likely to easily find electrolytics with voltage rating at anything over a few 100 volts ( up to ~ 500V are common and often used in SMPS's.
    But you need ones rated at several kV and that's why you use the appropriate rated disc ceramics

    I'm a little concerned that if you don't understand the basics like that, should you really be playing with HV ?
    please be very careful !

  7. May 24, 2014 #6


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  8. May 27, 2014 #7
    I appreciate the concerns. I am an electronics technician and have taken plenty of classes on the safety side of high voltage, the highest voltage I work with is about 270V DC. I have built a voltage multiplier in school with smaller potential, but they did not go into detail with it at all, it was just a quick lab. of corse I would limit the current to as low as a few mA to higher micro . definately wouldnt use mains, I plan on using a DC source and oscillator to a step up transformer. I do want to experiment with the high potential side of electronics. I dont plan on jumping straight into a circuit with that high amount of voltages just yet. I would like to practice and gradually get to the fun stuff with high respect to safety. the reason I was asking about the electrolytics is because I have never seen anything over 500V rating, but yet all i have seen is people using electrolytics, but any schematic I have seen, has never shown polarized caps. I guess my main question was do the ratings of the components need to be higher than the output? again thanks for any answers also I appreciate the concerns.
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