windell747
Mechanical
- Jun 16, 2005
- 64
I'm filtering a 1020Hz 3.3V squarewave from a microprosessor using a 2 pole low pass butterworth filter. Thanks to TI for their filter pro! I would like the output frequency of filter to be a 1020Hz sine wave. I realize that if I select the cutoff frequency at 1020Hz that my sine wave will be attenuated by -3dB. However, I would like this sine wave to be attenuated as little as possible.
By taking a look at the forier transform of a square wave I see the following beginning few terms...
4*k/(pi)*(sinx+0.33sin(3x)+0.2sin(5x)...)
So my understanding of the forier trasform is that I can set a cutoff frequency for the filter at 3*1020Hz (frequency of second term) and my output of the filter will be an unattenuated 1020Hz sine wave.
I would like to bounce this thought process off of you guys to see if this is a correct way to be thinking about getting an unattenuated sine wave. I'm new to filters...
I appreciate your guidance!
Thanks,
Windell
By taking a look at the forier transform of a square wave I see the following beginning few terms...
4*k/(pi)*(sinx+0.33sin(3x)+0.2sin(5x)...)
So my understanding of the forier trasform is that I can set a cutoff frequency for the filter at 3*1020Hz (frequency of second term) and my output of the filter will be an unattenuated 1020Hz sine wave.
I would like to bounce this thought process off of you guys to see if this is a correct way to be thinking about getting an unattenuated sine wave. I'm new to filters...
I appreciate your guidance!
Thanks,
Windell