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    negative miller capacitance in OTA

    what does the negative mean in OTA? and how can i to explain it ?

    thank you

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    Re: negative miller capacitance in OTA

    All transistors have Miller capacitance which is from the inverting output to the input. In a differential amp , by adding caps by cross over ( From + out to + in and -out to -in ) from internal differential outputs, it tends to cancel the negative feedback with a lesser positive feedback with non inverting current or negative Miller Effect .

    When done right, with very low connection ESR you get extended bandwidth and it remains stable.
    A good design question lists your overall requirements™ The best question deserves a better answer. ™
    ... Tony Stewart EE since 1975


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    Re: negative miller capacitance in OTA

    thank you for reply
    you mean that i have to connect the output and input capacitor(miller capacitor) opposite input and output of OTA



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    Re: negative miller capacitance in OTA

    Quote Originally Posted by muhaned View Post
    thank you for reply
    you mean that i have to connect the output and input capacitor(miller capacitor) opposite input and output of OTA
    You are advised to apply this principle inside a differential output OTA, due to parasitic effects of layout and likely instabilities otherwise neglected.

    Do you understand Negative Miller Effect is positive feedback?
    A good design question lists your overall requirements™ The best question deserves a better answer. ™
    ... Tony Stewart EE since 1975



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