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Miller Capacitance and its use in Differential Amplifier

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graciousparul

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Miller capacitance

Hi,

What is Miller Capacitance? Why it is used in Differential Amplifier?
 

A.Anand Srinivasan

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Miller capacitance

miller capacitance is the increase in the value of a capacitor connected between the output and input due to the gain of the system.... this leads to shorting of input and output at high frequency leading to reduction in gain at high frequencies
 

FvM

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Re: Miller capacitance

Hello,

miller capacitance appears both as unwanted effect that degrades preformance of amplifiers and as means in circuit design to achieve a particular frequency characteristic. When designing e. g. operational amplifiers frequency compensation, you can create a dominant pole by artificially increasing an already existing miller capacitance, simultaneously eliminating additional higher oder poles.

Regards,
Frank
 

a_tek7

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Re: Miller capacitance

1.isolation of poles
2.improvment of open loop gain
3.improvment of BW(Bandwidth)
4.we make a small capacitane & miller effect provide a bigger one(application:IC)
 

linkfox

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Re: Miller capacitance

graciousparul said:
Hi,

What is Miller Capacitance? Why it is used in Differential Amplifier?

a useful tutorial might be useful !
 

tom.73545

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Miller capacitance

Thanks for the tutorial!
 

LvW

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Re: Miller capacitance

One additional hint:

The very well known inverting MILLER integrator is equivalent to a simple RC low pass with a capacitance which is increased by a factor Ao (opamp open loop gain).
This increase is due to the MILLER effect.
 

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