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DC-DC power conversion and voltage regulators

  1. May 6, 2012 #1
    dear Experts

    Voltage regulators maintain steady output voltage.
    DC-DC step up or down converters (aka inverting switching regulators or boost converters) act like DC 'transformers'.

    I like to confirm that when I step down voltage, the current will increase when i use either of them.

    Which is more efficient in increasing the current for step-down scenarios?

    Please could you comment on this?

    Thanks very much.

    Best regards
  2. jcsd
  3. May 6, 2012 #2


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    Gold Member

    Hi Ramone! Please refrain from inventing new terms like "DC transformers". To communicate clearly in the electronics world we all need to use the same terms with definitions agreed upon. This is how we avoid misunderstandings and miscommunications.

    "A DC-to-DC converter is an electronic circuit which converts a source of direct current (DC) from one voltage level to another. It is a class of power converter."

    As for increasing the current, that always depends on several variables, so it is impossible to directly answer your questiion. If we specify the load resistance, the converter's output capacity, etc., then we could begin to predict output current.

    As for efficiency, some types are notorious for being inefficient, but used anyway for various reasons. In other cases like battery operated devices, different types are used because they are more efficient. Study the various types and their efficency.

    And if you have any more questions or doubts, come right back here and post them.

  4. May 6, 2012 #3


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    Staff: Mentor

    In general that's true, though the circuit takes some power for its own use and to account for losses as heat. What DC levels are you interested in dropping from and to, and at what currents?
  5. May 12, 2012 #4
    Hello NascentOxygen

    Thanks for your reply.
    The DC levels I am interested in are :

    From 9V DC to 6V DC.


    Hi BobbyWhy
    So sorry for using the wrong terms . I have noted and will refrain from using improper terms.
    I did not mean to purposely confuse people. I am not very knowledgeable in this area.

    Have a nice day.

  6. May 12, 2012 #5


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    Gold Member

    Hey Ramone! Spoken like a true scientist or engineer!

    Cheers, Bobbywhy
  7. May 12, 2012 #6


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    Staff: Mentor

    If the current will be more than say, 100mA, then a switching regulator should do the job okay. For lesser currents, you could discard the excess using a 3V zener diode, this may be about as efficient (0.3W losses).
    Last edited: May 12, 2012
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