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Homework Help: 555 monostable

  1. Jul 12, 2010 #1
    1. The problem statement, all variables and given/known data

    Design a 555-based monostable which outputs a constant pulse 3.3s long each time a button is pressed (whether the button is pressed briefly or held down). Use a 1µF timing capacitor. Indicate all component values. What voltage should be applied to pin 5 to double the output pulse duration?

    2. Relevant equations


    3. The attempt at a solution

    How does the 0.1µF capacitor help output a single pulse (whether the button is pressed briefly/held down)? In my notes it said that if RC (of 0.1µF capacitor and 10k resistor) < RC of monostable (1%), the timing period will stay the same whether the input remains low or goes low briefly. I dont really understand this.

    Attached Files:

  2. jcsd
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