DC Power Supply

Discussion in 'The Projects Forum' started by clear856, Mar 1, 2011.

  1. clear856

    Thread Starter New Member

    Mar 1, 2011
    2
    0
    Hello

    I am conducting research in which I electro etch materials. For one technique I need a power supply that can output a constant current into multiple channels. However, all channels come in contact with the same etching bath and lead to only one cathode.

    I was wondering if there is a way to supply a constant current to all channels even though they all come in electrical contact with one another when their respective anodes are lowered into an electrolytic bath.

    How would such a power supply be designed?
    I am not too familiar with these sorts of things, and the electronics shop manager in charge of making the power supply is not exactly sure how to put one together for this application.

    Any help would be appreciated

    Cheers
     
  2. wayneh

    Expert

    Sep 9, 2010
    12,103
    3,038
    Multiple channels is not a problem - you'll need a control on each - but how much current are you looking for? And what sort of supply do you have?

    And welcome to the AAC forum!
     
  3. Wendy

    Moderator

    Mar 24, 2008
    20,765
    2,536
    Do you want each channel to be a separate current, or one constant current.

    There are many ways to do this, most are pretty good, but we need the magnitude of the current (what wayneh said).
     
  4. clear856

    Thread Starter New Member

    Mar 1, 2011
    2
    0
    each channel should have a constant current of up to 100 mA
     
  5. Wendy

    Moderator

    Mar 24, 2008
    20,765
    2,536
    And the minimum? 0 is doable, but setting it to a number makes it a bit easier.
     
  6. Wendy

    Moderator

    Mar 24, 2008
    20,765
    2,536
    BTW, here is a simple one, I assume you need a source.

    Up R1 to 10Ω, it will be 0 - 600 ma. If R1 is 56Ω it will be 0 - 110ma.

    [​IMG]

    Max current = 0.6V / R1
     
    Last edited: Mar 4, 2011
  7. wayneh

    Expert

    Sep 9, 2010
    12,103
    3,038
    Here's a more elaborate version. You may need to experiment a bit with the shunt resistor (shown as 1 ohm) and the current limiting resistor, if needed. Also, you could certainly use a single power supply (at 12v, eliminating the 5v reference) but it would need to be regulated at some voltage to act as voltage reference.

    Picture 3.png
     
Loading...