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  1. #1
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    fully differential opamp' s output is not symmetrical

    dear friends:

    the tran simulation of a fully differential opamp likes the following figure, the frequency of input signal is 5MHZ to obtain figure.1 and it is 100hz with figure.3. could you explain why it is not symmetrical at the begin, I wonder why it is not similiar with figure. 3. thank you very much.

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    figure. 1 outputs of opamp
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    figure. 2 schematic of opamp
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    figure. 3

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  2. #2
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    Re: fully differential opamp' s output is not symmetrical

    Apparently an AC coupled test setup. Looks like normal operation.



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  3. #3
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    Re: fully differential opamp' s output is not symmetrical

    dear FvM:
    thank you for your reply. can I think that is a normal results? if it is, could you tell me the reson about the undifference befor 1ms as shown in figure. 1.



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  4. #4
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    Re: fully differential opamp' s output is not symmetrical

    Take a simple RC circuit and give it a square wave periodic input. It will take sometime for the output to settle to a periodic waveform. Its similar here.



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    Re: fully differential opamp' s output is not symmetrical

    All electrical circuits have "Temporary Time Regime" at the beginning.



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  6. #6
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    Re: fully differential opamp' s output is not symmetrical

    thanks for all of you, I have got the reason



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