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    digital potentiometer

    hai bro i want make digital potentiometer use similiar part and design. the number of potentiometer show in 7 segmen but not with microprocessor. if somebody know about this please share with me.
    tanx

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    digital potentiometer

    It surely can work with discrete logic devices, e. g. CD4000 or 74HC family, but the part count must be expected much higher than with a microprocessor, that would allow true single chip designs. But it had been the usual way some decades ago.



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    digital potentiometer

    do you know the circuit about it



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    Re: digital potentiometer

    I don't know what you're going to use your digital potmeter for. But have you considered if it will work with a variable current sink?

    Then you can have an arbitrary number of bits in that is used to control the output current.

    You need:
    * a simple DA converter (a handful of resistors - R + 2R)
    * Opamp
    * BJT transistor and a resistor (low value) where voltage over thhis resistor makes the current.



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    digital potentiometer

    what kind of series are for the component?



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    Re: digital potentiometer

    Quote Originally Posted by ranggaperdana_06114
    what kind of series are for the component?
    About any opamp will work.
    Beside that, you use just regular resistors and buffer. Good choice could be R=10kΩ

    You're free to decide if 2R would be two resistors in serie or if R would be two in parallel. You won't get combination R and 2R out of the usual E12 serie.

    And for the buffer you can the TTL circuit 7407.



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    Re: digital potentiometer

    Perhaps this circuit would be of help:



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    digital potentiometer

    can you tell how it's works ?



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