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Dual DC power supply

  1. Jan 14, 2012 #1
    Hi,i really need help on how to design a dual channel DC power supply that fulfills the following specifications :

    1) Operation - User selection between independent adjustment for positive and negative output voltage, and series tracking mode (slave channel tracks the master channel)

    2) Output voltage amplitude : 0-20V± 5%

    3) Current limit : 0 - 1.5A± 10%

    4) Powered Directly from main supply

    5) Indications of power on, constant voltage and constant current mode

    I really hope you guys will be able to help me and provide me with a schematic to achieve the above specifications..thanks in advance =)
  2. jcsd
  3. Jan 14, 2012 #2
    I have found the schematic from this link http://www.aaroncake.net/circuits/supply3.asp
    but i would like to know how to make the circuit to produce an output voltage of 0-20V instead of just 0-15v?can anyone give me any helpful suggestions?
  4. Jan 14, 2012 #3

    jim hardy

    User Avatar
    Science Advisor
    Gold Member

    that schematic should produce from 1.2 to 27 volts.

    check datasheet for your regulator.

    EDIT make that "that schematic should produce from 1.2 to about 19 volts.

    what limits it to 19V is volts available from transformer.
    15 X sqr(2) = 21 volts, less drop across bridge.

    use a higher voltage transformer, something like this:
    http://www.allelectronics.com/make-a-store/item/TX-398/POWER-TRANSFORMER-39.8V/22.5V-2.25A/1.html [Broken]

    and you should do fine.
    Last edited by a moderator: May 5, 2017
  5. Jan 14, 2012 #4
    wow..thanks a lot..appreciate it =)
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