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    Capacitor connected to Supply voltage in RC Integrator

    Why in RC Integrator circuits , Caps are connected sometimes to supply voltage instead of ground ?

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    Re: Capacitor connected to Supply voltage in RC Integrator

    Hi,

    Measure the voltage at the capacitor wrt GND immediately after power up.

    One time it is low, the other time it is high...

    Klaus



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    Re: Capacitor connected to Supply voltage in RC Integrator

    Quote Originally Posted by KlausST View Post
    Hi,

    Measure the voltage at the capacitor wrt GND immediately after power up.

    One time it is low, the other time it is high...

    Klaus
    Sorry But I don't get it

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    Here is what I meant , Why to connect capacitor to Vdd instead of connecting it to ground ?



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    Re: Capacitor connected to Supply voltage in RC Integrator

    Where you connect the capacitor only has a significant effect upon power up (assuming the power supply has no significant AC noise on it).
    If you connect the capacitor to ground, the capacitor voltage will remain at 0V when circuit power is applied.
    If connected to power, then the capacitor voltage will immediately go to the supply voltage when power is applied (since voltage across a capacitor cannot instantly change).
    Zapper
    Curmudgeon Elektroniker



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    Re: Capacitor connected to Supply voltage in RC Integrator

    Great . I understand , Im missing what benefit do I get from this ?



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    Re: Capacitor connected to Supply voltage in RC Integrator

    To force logic 1 initial condition on power up
    A good design question lists your overall requirements™ The best question deserves a better answer. ™
    ... Tony Stewart EE since 1975



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