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Current peak delay after voltage peak

  1. Jun 9, 2014 #1
    Hello. So when you apply a square wave of voltage to a circuit, there is a slight delay for the electrical current. I'm trying to understand this concept better. I'd like to know if this delay is shorter with wire diameter.. if higher voltage decreases the delay time.. etc. Is there a name for this concept so I can read about it? Thank you.
  2. jcsd
  3. Jun 9, 2014 #2
    all circuits have capacitive and inductive components to them. Capacitors delay changes in voltage until energy is stored or released in them in the form of an electric field. Inductors delay changes in current by storing energy in a magnetic field. The delay is usually called the phase angle when you have continuously changing signal.

    If you are dealing with digital electronics, you are also dealing with propagation delay which includes some pretty complex quantum stuff. Even more significant, you have to give the logic circuits time to stabilize.
  4. Jun 9, 2014 #3


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    Staff: Mentor

    All devices and wiring have stray capacitance along the way, and there is an inevitable delay while this cpacitance is being charged. The capacitance can be dependant upon dimensions of the conductor, and proximity to other conductors. It is not dependent on voltage level in wiring, etc., but inside semiconductor devices it certainly can be voltage dependent.

    The delay is present for all changing signals, not just squarewaves, though it is more obvious and readily demonstrated by using squarewaves or rectangular waves.

    MrSparkle illuminated the topic well.
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