What’s the difference between Noise Gain & Signal Gain o

[ZengLei]

We all know that in the two negative-feedback circuit
It’s easy to figure out the Voltage-Gain (Signal Gain)
1. （R1+R2）/R1
2. -R2/R1;

But here I see a terminology “Noise Gain” which is totally new for me
It says the Noise Gain of the two circuits is the same
Noise Gain= (R1+R2)/R1;
Here I got confused!!
What the Noise Gain is? What’s the definition of a noise gain?
How to calculate it…..
What’s the difference between Noise Gain & Signal Gain of an OP-circuit??
Thanks~~~~~~~~

 

[claudiocamera]

Check this page and see if it helps:

https://www.analog.com/library/analogDialogue/Anniversary/8.html

 

[A.Anand Srinivasan]

Re: What’s the difference between Noise Gain &

try this link.,....

**broken link removed**

 

[Analog Convict]

Re: What’s the difference between Noise Gain & Signal Gain

https://www.jensign.com/noisegain/index.html