advantages of using an inverting op-amp

[siongboon]

Hi,

I could not find notes regarding the advantages of using a inverting op-amp as an amplifier compare to the non-inverting op-amp.
I believe there should be some.
Would like to ask if you can list some points for my references.

Thank you.
Siong Boon

 

[LvW]

Where does your believe comes from?
For my opinion, there are no particular "advantages" of the inverting configuration if compared with the non-inv. version.
In contrast, the input resistance of the non-inv. opamp configuration is much larger than that of the inverter.
However, in some cases a phase inversion is needed for stability reasons - for example in feedback loops that contain several blocks.
In this case, an inverting configuration is one possible solution.

 

[siongboon]

Ya. Stable was the keyword I was looking for, but I couldn't find the relevant information.
I was taught in school that inverting configuration is more stable.
This mindset has been with me ever since.
I do not have the full understanding of the theory but I still remember about the advantage of being stable. Now that you have mentioned it, I felt much more comfortable about my memory.

My recent study shows that non-inverting op-amp is in fact better.
That was why I have been looking for information about the advantage of using a inverting op-amp. As much as possible, all design should consider non-inverting op-amp first as recommended on many of the website.

Thank you very much.

 

[LvW]

I was taught in school that inverting configuration is more stable.

That's not true. Both versions - inverting and non-inverting - need negative feedback.
The only difference is (a) that the non-inv. cicuit's gain is larger by "+1" if compared with the inv. opamp and (b) the larger input resistance.
Stability properties are exactly the same if the loop gain is the same.

- - - Updated - - -

Remark: Perhaps you have learned the following (which is correct): Negative feedback makes the dc operating point more stable, but - at the same time - the dynamic stability (against self-oscillations) is reduced.

 

[siongboon]

I must have learn and remember the wrong thing.
Time to put in more effort.