Wednesday, 13 February 2013

NE555 Voltage Doubler

Here's a cheaper-to-build alternative for MAX1044/ICL7660 voltage doubler charge pump. According to the documentation, this puppy is capable of 30mA of output current, so it'll be enough for any stompbox use. Circuit isn't as small, as using NE555 timer chip will need couple of resistors and caps to get the job done. Still, simple and small enough.


27 comments:

  1. Are the NE555 and LM555 chips interchangeable?

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    Replies
    1. Same circuit, different manufacturer. First listed feature from the LM555 datasheet:
      -Direct replacement for SE555/NE555
      http://www.physics.rutgers.edu/rcem/~ahogan/327/LM555.pdf
      +m

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  2. Is this any noisier than the other pumps?

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    Replies
    1. Shouldn't be. But i wouldn't know as i haven't built one yet...
      +m

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    2. Well i'll let you know later

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  3. I'm building a delay that requires ~35mA at 18v. Could two of these be put in parallel if higher current is required?

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    Replies
    1. I have no idea if that would work. Sorry..
      +m

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  4. Can i use this doubler with a 9v battery or only with a power supply ?

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  5. would this work with 12V to give out 24v? how many mA?

    thanks

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    Replies
    1. http://www.eleccircuit.com/wp-content/uploads/2010/05/doubler-voltage-12vdc-to-24vdc-with-ne555.jpg

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  6. Verified. w/ a 9v power supply reading at 10.4v I ended up with 20.5v at the output. Very low noise also... I ran out of DC jacks and had to wire the output directly into an OCD clone to test out in circuit but I don't see it having any affect on noise going through the jack to jack route. I recommend this one to the ICL7660 pumps as its the same quality at a fraction of the cost.....I got my NE555 stock for $0.14 a piece.

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  7. Hello,
    is there a compact way to apply a voltage doubler and an inverter to get +/- 18V (for an EHX equalizer) from a +9V power supply? thank you!

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  8. Would this pump fit into a altoids tin or something of similar size with 2x 2.1mm jacks?

    I'd love to stick this into something crazy small to velcro it to the under side of one of my pedal board rails.

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  9. Hi everyone
    i have build this charge pump twice and it dose not worked and it just puts out 9v
    Any ideas
    tnx

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    Replies
    1. Check your layout and wire connections. The 9v rail is right next to the 18V rail, so be sure you grabbed the right rail.

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    2. i have checked the board many times and cant find anything wrong with it even went between the cooper strips with a knife to make sure there is no connection between any of them.i have build many pedals and i don't get why this one is not working
      tnx anyway

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    3. I've built this pump succesfully, getting up to 24 volts out of the output....the layout is def verified...id check usuals, capacitors, resistors, polarity of caps and in/out plugs, track cuts/bridges.....if you can host pics of your build ill take a look and see if anything looks out of the normal....hope it works out for you


      -Adam

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    4. mike

      This is gonna sound dumb, but on my first charge pump build, I was only getting 9v on the out. Turns out I didn't have the ground connected while testing. When I grounded it properly, out came the 18v. Just throwing that out just in case....

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    5. sorry - actually meant that comment directed to strat...

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  10. Does anyone have the Schematic? I do like!

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  11. This might be a silly question but... Is it possible to incorporate a sag pot on this? I'm looking for something similar to Beavis Audio's Devolt (or whatever it's called), but I'd love to be able to start at 18v for a couple pedals. I can definitely just add the sag after this circuit, but I was wondering if one of the resistors could just be replaced with a pot to keep the size down as I might have a few of these on my board. Thanks!

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  12. I'd like to power a pedal to 18 volts maximum (an univibe); is this charge pump ok for this? I've red that arrives to 24 volts....can I get down this value in any way?
    thanks friends! :)

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  13. What an amazing and useful site. IvIark deserves a tech Grammy.

    QUESTION ABOUT HIGH-PITCHED WHINE.

    I have built three of these voltage doublers. Two were fine; the third one is doing that high-pitched-whine thing. Only happens when I switch to 18v - I have the doubler on a DPDT. Everything about the build, and the pedal it's in, is essentially the same as the last two. I've tried: replacing the 555; going over all soldering, channels, etc; adding decoupling cap and resistor at the positive input, moving the whole unit around.... nothing changes it. The incoming power supply is a One-Spot, and I've used two other adapters, not daisy-chained. The voltage out is correct -- around 17v or a bit higher. Used 1N4001 diodes.

    Is there any other possible fix or should I toss it into the Box Of Inexplicable Weirdness?

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  14. Hey All

    Not to dig up an old layout but does anyone know where the original schematic for this is? I have searched anywhere I can think of (incl. other forums) and checked google images and cannot seem to find an exact match. I have found similar but not one with these parts values. Might be a stretch I know. It appears to be the one Miro posted a while back with different values... is this correct? :)

    http://www.eleccircuit.com/wp-content/uploads/2010/05/doubler-voltage-12vdc-to-24vdc-with-ne555.jpg

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