Custom dm8k psu

Discussion in 'Hardware troubles and Repair support.' started by misiozol, Apr 20, 2016.

  1. misiozol

    misiozol New Member

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    So I have seen it on other forum chap is from china it's looking nice and tidy but could not contact him for over a 2 years , any one had a chance even to create their own custom psu , I'm planing to use small electronic pc psu and just add 2 stepdowns for 2.5 voltages
     
  2. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Replace certain voltages, for an alternative source is of course possible.
    So I like working with the Dc-Dc converter adjustable step-down module to replace a voltage.
    As I have used/done for the 800hd
    But usually when the original source is not repairable because ic can not be found or to much damages.

    Furthermore, you have to deal with the 8k box with the power consumption.
    You will first need to know how much the x voltage ask to be able to replace it.
    And some voltage are frequency sensitive.

    In other words, yes it will be possible.
    But not easy to do.
     
  3. misiozol

    misiozol New Member

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    I was planning to use 14V external universal laptop psu , use it to supply power 14v from what i remember 14v is permanent and supply power for micro PC psu to get 3.3v 5v and 12v and use lm2579 or similar to get 2.5v it has about 3A , and one fotorelay to enable pc psu pin 14 as it need low to enable and dm8k has 3.3v (high) to enable instead of low , u can get micro 160w pc psu for ~17e from aliexpress should be simple just curious if any one tried it ;)
     
  4. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Yes the 14 v 3 amps could be sufficient to be able to create the other voltages.
    But my preference is a 4 or 5Amps, with overload and short circuit protection.

    Anyway, I have enough 8k PSUs, so I have no need to build one.
    But it is an interesting thought.
     
  5. misiozol

    misiozol New Member

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    I was thinking about 3amps only for 2.5v as laptop psu can generate ~7-8A , and micro PC psu will have about 160W , will use step down from 3.3v to 2.5v to limit heat production , I was thinking about it for long time how to make it simple , and this is basic and simple with minimal elements need , and should be much less heat in side dm8k ;) , have seen couple of custom dm8k psu and it seems that this option is most simple and realistic .
     
  6. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Yeah okay, I would test it first with an adjustable lab power supply before I would build something.
    Then I also know the amps consumption for this circuit.