• bleistift2@feddit.de
    link
    fedilink
    English
    arrow-up
    6
    ·
    edit-2
    9 months ago

    If the rise time isn’t 0, it’s not a square wave.

    Also (honest question): Is this a hard thing to do in engineering? What makes it hard?

    • stevestevesteve@lemmy.world
      link
      fedilink
      arrow-up
      50
      ·
      9 months ago

      If the rise time isn’t 0, it’s not a square wave.

      And if that’s your definition then there’s no such thing as a real square wave.

      Just like no physical objects can have a perfectly square corner, there will always be some radius, even if it’s just 1 atom

      The reason making a true square wave is hard is that there are physical properties of real life electrical components that prevent voltage (or current) from changing instantly. Similar to how we can’t instantly accelerate a mass from 0 to some speed, it’s physically impossible. The faster you try to do it, the harder it is due to inertia. In electronics, there’s always natural capacitance and inductance slowing things down. If you want a 10v square wave, you have to push some amount of electrons through some amount of capacitance and inductance and that, while it can be very fast, is never instant.

      • bleistift2@feddit.de
        link
        fedilink
        English
        arrow-up
        22
        ·
        9 months ago

        The more I read of your answer the more I think I should’ve come to that conclusion myself.

    • Num10ck@lemmy.world
      link
      fedilink
      English
      arrow-up
      29
      ·
      9 months ago

      if you get deep enough into software you realize its all ones and zeroes.

      if you get deep enough into electronics you learn there’s actually no such thing as a 1 or 0. check out the bit error rate of an eye diagram.

    • Holzkohlen@feddit.de
      link
      fedilink
      arrow-up
      15
      ·
      9 months ago

      lol 0.02 microseconds is 0.00000002 seconds. Don’t know electronics tho. No idea what exactly makes it difficult.

      • verdare [he/him]@beehaw.org
        link
        fedilink
        arrow-up
        3
        ·
        9 months ago

        It’s difficult because a rise time of zero is physically impossible. You can’t instantaneously jump from one voltage to another in real life; There’s always a transient response. Circuits are made of physical components and electrons are moving objects.