Lowpass filter design

[zawminoo]

Hi,

I designed a fourth order butterworth low pass filter at cutoff frequency =10Hz. All resistance values are 82 kΩ.
And for a unity gain.I made if for noise remove.
But there are difference my design and my friend.
Who is right? Why?
If not please design it.

First design(my friend)
C1A=183 πF
C1B= 150 nF
C2A= 470 nF
C2B= 68 nF
Second design(I)
C1A=210 πF
C1B= 179 nF
C2A= 507 nF
C2B= 74 nF

 

[gwj221]

butterworth

R AND C SELECT:

R = R

C1B = C1A/2