Hello All,
I would like to get some clarifications related to operational amplifiers, as listed below,
Ringing effect: in the analysis of an op-amp, it is seen that when an input is step then output will not smoothly follow input but
there can be ringing effect around the max value, before output settles to input value. Of course, this is with appropriate amplification.
Now, if input is varying (say a simple sinusoidal input) then this means that as input keeps varying, output does follow input with appropriate scaling.
However, output also does not follow input smoothly but with distortions. Is this correct?
I have uploaded a sample image (named capture) that has input and output. Please note that, I have kept gain = 1 to keep things simple.
Phase response: the phase of of amplifiers reduces as frequency increases. I don't know if phase lag is an absolute value or a function of frequency itself.
But if input contains multiple frequency components (which is the case with natural signals), as they pass through the amplifier, each frequency component undergoes varying phase lag. So, each frequency component does get amplified but is output with varying delays.
Hence effectively the shape of the signal would change if one were to assume that the effect of the amplifier is same as adding each of these frequency components after amplification
Integrator: conceptually, is an integrator used in amplifier a sort of accumulator, where output is not proportional to current input but
is current value + delta?
Delta is proportional to input.
Time constant: what really is a time constant of a system?
Order of the system: what is an order of a system and how it can be computed?
Infinite input/output resistance: in description of amplifiers, reference is made to input and output resistances being infinite.
I am not able to appreciate what this means. Can I get some simple explanation with an example?
Amplifier design: in certain amplifier description, the design itself contains another amplifier. I believe this is done for integrator or voltage buffer (I am not too sure). So, how does it work? An amplifier needs another amplifier?
Amplification: this is more of a conceptual (and probably philosophical) question. It one were to amplify an input, one cannot do this using just an input alone. For example, if an input current needs to be amplified then one would need additional current source to do this and input alone is not sufficient.
A simplistic amplifier shows integrator as the key block that amplifier input value. But since this is just a passive element, where does additional current/voltage that is present in the output come from?
Thanks for your time ...
I would like to get some clarifications related to operational amplifiers, as listed below,
Ringing effect: in the analysis of an op-amp, it is seen that when an input is step then output will not smoothly follow input but
there can be ringing effect around the max value, before output settles to input value. Of course, this is with appropriate amplification.
Now, if input is varying (say a simple sinusoidal input) then this means that as input keeps varying, output does follow input with appropriate scaling.
However, output also does not follow input smoothly but with distortions. Is this correct?
I have uploaded a sample image (named capture) that has input and output. Please note that, I have kept gain = 1 to keep things simple.
Phase response: the phase of of amplifiers reduces as frequency increases. I don't know if phase lag is an absolute value or a function of frequency itself.
But if input contains multiple frequency components (which is the case with natural signals), as they pass through the amplifier, each frequency component undergoes varying phase lag. So, each frequency component does get amplified but is output with varying delays.
Hence effectively the shape of the signal would change if one were to assume that the effect of the amplifier is same as adding each of these frequency components after amplification
Integrator: conceptually, is an integrator used in amplifier a sort of accumulator, where output is not proportional to current input but
is current value + delta?
Delta is proportional to input.
Time constant: what really is a time constant of a system?
Order of the system: what is an order of a system and how it can be computed?
Infinite input/output resistance: in description of amplifiers, reference is made to input and output resistances being infinite.
I am not able to appreciate what this means. Can I get some simple explanation with an example?
Amplifier design: in certain amplifier description, the design itself contains another amplifier. I believe this is done for integrator or voltage buffer (I am not too sure). So, how does it work? An amplifier needs another amplifier?
Amplification: this is more of a conceptual (and probably philosophical) question. It one were to amplify an input, one cannot do this using just an input alone. For example, if an input current needs to be amplified then one would need additional current source to do this and input alone is not sufficient.
A simplistic amplifier shows integrator as the key block that amplifier input value. But since this is just a passive element, where does additional current/voltage that is present in the output come from?
Thanks for your time ...
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