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    Can I use a digital potentiometer replace the potentiometer in a buck converter board

    The LM2596 Adjustable DC-DC Buck Converter Step Down Voltage Regulator:

    https://www.ebay.com/itm/LM2596-Adju...AAAOSwoydWmsdS

    Thanks

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    Re: Can I use a digital potentiometer replace the potentiometer in a buck converter b

    Hi,

    First you need the schematic of the module to know about the pot's signals (voltages and currents).
    Then read the digital post's datasheet to get information about it's power supply requirements and signal limits.
    How do you consider to generate the power supply?
    Are the module voltages and currents all within the pot's specifications?

    Klaus
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    Re: Can I use a digital potentiometer replace the potentiometer in a buck converter b

    Quote Originally Posted by KlausST View Post
    Hi,

    First you need the schematic of the module to know about the pot's signals (voltages and currents).
    Then read the digital post's datasheet to get information about it's power supply requirements and signal limits.
    How do you consider to generate the power supply?
    Are the module voltages and currents all within the pot's specifications?

    Klaus
    Thank you.
    The attached is the circuit of the LM2596 Adjustable Converter, there is no datasheet, don't how to figure out the pot's signals.

    https://imgur.com/a/cvTG3Lw



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    Re: Can I use a digital potentiometer replace the potentiometer in a buck converter b

    Hi,

    there is no datasheet
    every IC and every electronic part comes with a datasheet.

    don't how to figure out the pot's signals
    Hopefully you can identify the pot in the linked schematic.
    It is connected to the FB pin of the regulator --> look at the regulator datasheet about FB pin voltage
    The other side is connected to the output voltage --> the output voltage range is given in the schematic

    Klaus
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    Re: Can I use a digital potentiometer replace the potentiometer in a buck converter b

    It would be difficult to replace the potentiometer with a digital one in that schematic because of the high voltages it would have to endure. You could 'reverse' the feedback by swapping R1 and R2, it would at least let you ground reference the digital pot but it would work 'backwards' compared to the present position and to some degree sacrifice the ability to stabilize the output voltage.

    A better method would be to use a DAC to drive the FB pin to set the voltage and also sense the output to maintain regulation.

    Brian.
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    Re: Can I use a digital potentiometer replace the potentiometer in a buck converter b




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