Boost 12V dc to 48V dc

Discussion in 'General Electronics Chat' started by king40, Jan 17, 2014.

  1. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    Hi
    Engineers and friends
    I need a way to boost 12v dc to 48V dc
    Please help me :rolleyes:
    Thanks
     
  2. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    available source current?
    required output current?
     
    king40 likes this.
  3. Gibson486

    Member

    Jul 20, 2012
    199
    12
    boost converter. It is possible. Just remember, power in equals power out.
     
    king40 likes this.
  4. Papabravo

    Expert

    Feb 24, 2006
    10,135
    1,786
    Not quite. Power out will always be less than power in. They will be equal only in an ideal universe, which this one unfortunately is not. I like to use 80% as a "rule of thumb" efficiency for a boost SMPS.
     
    king40 likes this.
  5. inwo

    Well-Known Member

    Nov 7, 2013
    2,433
    315
    Does anyone know if any of the inexpensive boost converters have isolated outputs? (use transformer)

    They generally only go to 36v out.

    If they could be connected in tandem it would open up the possibility of higher outputs.
     
    king40 likes this.
  6. MrChips

    Moderator

    Oct 2, 2009
    12,415
    3,354
    Just as an example, if your load requires 1A@48V you will need to supply about 5A@12V.
     
    king40 likes this.
  7. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    Hi friends
    Source is 12v, 1.2mA
    And output 48v and amper not important
    Thanks All
     
  8. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    Why don't you explain "in detail" exactly what you are trying to do with this 48V signal and what are the details on this 12V source?
     
    king40 likes this.
  9. bertus

    Administrator

    Apr 5, 2008
    15,638
    2,344
    Hello,

    I think this thread is the sucessor of his previous thread:
    simply convert 12v dc to 300v

    It looks like he is going lower and lower on the output voltage.

    Bertus
     
    king40 likes this.
  10. bountyhunter

    Well-Known Member

    Sep 7, 2009
    2,498
    507
    Then you will only get maybe 250 uA of current from the 48V side. You could just use a 555 free running (driving a 2N3904) with a coil/diode and a zener diode to clamp it at 48V.
     
    king40 likes this.
  11. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    Hi
    This is Separate of older thread
    Thanks
     
  12. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    Hi and thanks for answer
    This is exactly I want
    You can give me a circuit
    Thanks
     
  13. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    Instead of a 555 timer IC and a transistor, you can use two transistors like the schematic on this page;
    http://www.romanblack.com/smps/conv.htm

    However you will need to change a few resistor values to make it run from 12v 1.2mA, and of course the output zener diode needs to be changed to a 48v type.
     
    king40 likes this.
  14. bountyhunter

    Well-Known Member

    Sep 7, 2009
    2,498
    507
    Here is the basic circuit used in a circuit to boost 9V to about 39V (three 13V zener diodes in series clamp the voltage)..
     
    king40 likes this.
  15. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    thanks
    i simulation this circuit if proteus but not working :(
     
  16. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    thanks
    pwr=input voltage??
    where is the output voltage :D
     
  17. bountyhunter

    Well-Known Member

    Sep 7, 2009
    2,498
    507
    PWR is input, output is at the top of the three 13V zener diodes.
     
    king40 likes this.
  18. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    Then Proteus has failed or (more likely) YOU have failed to simulate it properly.

    The real circuit works well and has been built by many people. :)
     
    king40 likes this.
  19. king40

    Thread Starter Member

    Jul 17, 2013
    75
    0
    thanks
    yes i think i must test in real circuit

    here is proteus circuit and result:

    [​IMG]
     
    Last edited: Jan 19, 2014
Loading...