how to boost 3V DC to 6V DC?

Discussion in 'The Projects Forum' started by hemnath, Dec 18, 2012.

  1. hemnath

    Thread Starter New Member

    Dec 12, 2012
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    I have to boost the voltage from 3V to 6V and looked into boost converters ic such as maxim, Linear technology, Analog devices,etc... But it needs an extra device to my circuit and cost more.
    So I'm designing using simple joule thief. Is it possible to boost the voltage 3V to 6V using joule thief? else, is there any possible solutions to boost?

    Thanks in advance :)
     
  2. chunkmartinez

    Senior Member

    Jan 6, 2007
    180
    1
    Idk what joule theif is but I would look for one of those switching dc/dc boosters. They are much more efficient then most of the linear boosters.
     
  3. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,395
    1,607
    Assuming this is a very low current application a charge pump IC may better suit your needs. A device such as the MAX1682 voltage doubler just needs two 10uF caps to double the voltage, though it comes in a SOT-23-5 surface mounted package. It operates over a 2.0 to 5.5 V range.

    These devices work by charging one cap, then discharging that cap into another cap to get the double voltage.
     
  4. wayneh

    Expert

    Sep 9, 2010
    12,154
    3,060
    Those solar lights you see everywhere, which can be obtained cheaply of free, all use a simple boost circuit to light an LED from a single AA or AAA cell. If you supply one 3V, it'll easily give you 6V or more. Maybe that's all you need?
     
  5. JMac3108

    Active Member

    Aug 16, 2010
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    There is no such thing as a linear boost. All boost circuits require some sort of switching. If there is a linear boost that I'm not aware of, please post it and enlighten me :)
     
    #12 likes this.
  6. chunkmartinez

    Senior Member

    Jan 6, 2007
    180
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    They are called linear, reguardless which is why I called them that. Anyway, if they do require switching, where are the components like inductor, inside? And why are they so inefficient?
     
  7. #12

    Expert

    Nov 30, 2010
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    What are called linear? I'm having difficulty following you.
     
  8. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    Linear, schminear. I suggested a good and proper solution using a grand total of three components, by the way none of which is an inductor.

    Anyone have anything simpler?
     
  9. chunkmartinez

    Senior Member

    Jan 6, 2007
    180
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    Your idea sounds pretty good, I learned something today, or a few things..
     
  10. JMac3108

    Active Member

    Aug 16, 2010
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    Can you post a link to some type of boost that calls itself linear? I'd like to see it for my own education in case this ever comes up again. Thanks.
     
  11. JMac3108

    Active Member

    Aug 16, 2010
    349
    66
    To your efficiency question ...

    First off there is no such thing as a linear boost, so lets forget that and assume you're just generally asking about switching power suppy efficiency.

    A typical swithcing power supply can be 85% efficient, some better, some worse. This is quite good compared to a linear supply. Lets take a simple example of a linear regulator converting 12V to 5V with a 100mA load. THe efficiency is Pout/Pin = (5V)(100mA)/(12V)(500mA) = 5V/12V = 0.42 or 42% efficiency. This is pretty bad compared to a typical 85% in a switcher!
     
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