**Part Number:**OPA627

Hi Team,

I check the TI Precision Lab NOISE4. There are two stages Gain. I want to confirm the noise bandwidth for the first stage.

For the above

(1), If f1=10K, f2=100K, In order to calculate En_with_filter that is the firs stage output noise in the second stage. BWn1=SQRT(1.57*10K), BWn2=SQRT(1.57*100K)

En_with_filter=101*11*4.5 nV/SQRT(HZ)* BWn1 Or En_with_filter=101*11*4.5 nV/SQRT(HZ)* BWn2. Which is correct?

(1), If f1=100K, f2=10K, Then BWn1=SQRT(1.57*100K), BWn2=SQRT(1.57*10K),

En_with_filter=101*11*4.5 nV/SQRT(HZ)* BWn1 Or En_with_filter=101*11*4.5 nV/SQRT(HZ)* BWn2. Which is correct?