bipolar 50v variable circuit

Discussion in 'General Electronics Chat' started by mrmctackett, Jul 26, 2012.

  1. mrmctackett

    Thread Starter New Member

    Jul 25, 2012
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    guess use have all heard "im new to electronics a thousand times". sorry, but im another one.it would be much appreciated if any one can have a quick look at this dodgie drawing and criticise and or help out . Im tryn to make a variable bipolar power supply with low voltage/current drop to power some a small amplifier i have made and various other projects im learning. the itemes on the drawing are components i have lying around. [IMhttp://forum.allaboutcircuits.com/images/icons/icon11.gifG]file:///E:/img006.jpg[/IMG]
     
  2. mrmctackett

    Thread Starter New Member

    Jul 25, 2012
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    when i constructed them as two seperate supplies eg, pos supply and a neg supply they work under load just fine. but as soon as i construct using the common ground point adjusting one burns out the other 5kpot or 100 ohm resistor ?
     
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  3. shortbus

    AAC Fanatic!

    Sep 30, 2009
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  4. crutschow

    Expert

    Mar 14, 2008
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    You should look at the data sheets for the LM317 and the LM337. The Absolute Maximum Ratings for voltage are being significantly exceeded and the devices will likely fail at some point. Especially since a 52V transformer will give a peak rectified DC voltage of over 70V.

    As far as the pots burning out, that sounds like a wiring error.
     
  5. mrmctackett

    Thread Starter New Member

    Jul 25, 2012
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    the ct meets up with ground point on diagram( i should of drawn that sorry). I was hoping using pass transistors to carry most of the exceed lm317 lm337 volts/amps ratings would be a suitable solution. cheers for the input much appreciated , that has prompted me to find more suitable regulators for what im trying to achieve.
     
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