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about how to calculate the gain of op-amp

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466576266

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can anyone tell me how to calculate the gain of the circuit attanched here? thanks in advance.
 

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  • op_amp_calculation.bmp
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Hi,
Assuming both the terminals on the left have inputs. Calculate gain from each of them separately and add the expressions (superposition). If you are interested in just the DC gain then ignore the 150pF capacitors otherwise treat the parallel arrangement of the resistor and capacitor as a impedance and calculate the gain as a frequency dependent object.
The gain calculation is done just like you would do for an opamp circuit. Assuming the opamp gain is large the DC gain from the negative terminal to the output is -10K/2K = -5. Hope you can take it from here.
 
For DC calculation use this

DiffAmp.jpg

the two capacitors will reduce the gain as the frequency goes higher.

Alex
 
i get it .thank you.

---------- Post added at 11:54 ---------- Previous post was at 11:46 ----------

by the way,alex, how did u process the pic. i find my pic is much more larger than yours. and i like the way which u use.
 

Your picture is a bmp. Try saving as a png next time.
 

466576266 said:
by the way,alex, how did u process the pic. i find my pic is much more larger than yours. and i like the way which u use.
Click to expand...

The image size has nothing to do with the format, it can be changed in any image editor.
bmp is not a good format because of the large size and also many browsers will not open it.

The image thumbnail can be used with jpg, gif and maybe png.
Attach the images and the insert the images inline

Alex
 
thank u, alex.
and do u know the differences between common mode choke and differential mode. i want some materials about them . but i just cannt find some. can u give me some suggestions.
 

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