I'm getting confused. I'm trying to make a sallen key low pass filter where it's been established that R1 = R2 and C1 = C2.
ω = 1/sqrt(R*C)
Let's say I want to make an active lowpass filter that cuts out all frequencies above 400Hz.
With this in mind, I would do:
(1) 400 = 1/sqrt(R*C)
(2) plug in a random C value
(3) solve for the R.
I'm being told I'm off though. I hear that I actually need to do:
(4) ω = 2*∏*f
(5) put in 400 for the f and calculate ω
(6) do steps (2) and (3) as before
Steps (4) to (6) make no sense to me though. If I do this, wouldn't it would make my signal take longer to attenuate?
ω = 1/sqrt(R*C)
Let's say I want to make an active lowpass filter that cuts out all frequencies above 400Hz.
With this in mind, I would do:
(1) 400 = 1/sqrt(R*C)
(2) plug in a random C value
(3) solve for the R.
I'm being told I'm off though. I hear that I actually need to do:
(4) ω = 2*∏*f
(5) put in 400 for the f and calculate ω
(6) do steps (2) and (3) as before
Steps (4) to (6) make no sense to me though. If I do this, wouldn't it would make my signal take longer to attenuate?