-5V from +5V supply...

Discussion in 'General Electronics Chat' started by dtvonly, Feb 20, 2013.

  1. dtvonly

    Thread Starter Member

    Dec 14, 2012
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    Hi. Using discrete components (w/o any ICs like 7905), how can I get (or reverse) a +5V into a -5V supply? Please provide circuit or link to a circuit. Thank you.
     
  2. MrChips

    Moderator

    Oct 2, 2009
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  3. MrChips

    Moderator

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    If you have a restriction on using ICs, you can use a transistor oscillator driving a small transformer or a voltage doubler circuit.
     
  4. dtvonly

    Thread Starter Member

    Dec 14, 2012
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    Hello MrChips. One question about the devices you mentioned: what is the maximum current drive capability? The datasheets only mentioned supply current, voltages and test current of up to (only) 30mA. Is this the maximum for these devices?
     
  5. MrChips

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    Let's turn the question around. What current at -5V are you looking for?
     
  6. dtvonly

    Thread Starter Member

    Dec 14, 2012
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    Hi. I will need about 100mA. I can either buffer the output or use another inverting device, if there is one with higher output current drive.
     
  7. MrChips

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    100mA is substantial. You will need to build a switching supply.
     
  8. gootee

    Senior Member

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  9. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    Why can't you use ICs?

    Is this homework?
     
  10. t06afre

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    May 11, 2009
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