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Tobias
- 23rd August 2008, 20:40
HI
I am turning a 5v signal on and off around 700 hz is the max. I need to get a filter going to average out this pulse. The duty cycle will be between 22 and 66. Any ideas as to where I can get info for a starting point?
Thanks
Toby

mat janssen
- 24th August 2008, 10:26
When you build a low pass rc filter with and RC time of 1/5 th of the freq. the ripple would be very small.
Your case:
700Hz = 1,43 msec
5 x 1,43 = 7,15 msec
R x C should be about 7,15 msec
330 nF and 22Kohm gives you 7,26 msec.