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question about RC osillator

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janet

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what will happen if the initial value of each invetor look like this??
 
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The two inverters that have the same input and ouput levels will switch causing the structure to oscillate since the number of inverters is odd.
 

now,if the initial value of each invertor isn't logical right(just as the picture shown),will the osc operate at another frequency other than it's nominal frequency?
 

Ring oscillators are known to oscillate at a frequency determined by the total delay, after a transitional state, the circuit is supposed to reach this stable state. It may be difficult however, to estimate the duration of transitional state, it's a problem similar to analysis of metastability, I think.
 

    janet

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I have designed a invertor osc , it's nominal frequency is 2MHz,but when I first power off OSC,then power on it, it's frequency has the chance to be reach up to 6.xMHz.
I wonder whether the changing of initial valuve lead th this problem??because when it's pow off,it has uncertain initial value.
 

You see this in real operation, not a simulation? You get different, arbitrary frequencies?

P.S.: And stationary?
 

    janet

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yes, my design target is 2.3MHz, but test result is 6.XMHz.
And my RC OSC donot have definite initial value,so I doubt whether it's incorrect initial value lead to the bad result.
 

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