The typical frequency of a Arduino PWM pin is 490Hz.
Are you saying a PWM signal comprises of all frequencies up to 490Hz (see attached)
and the filter 'highlights' the frequency we're interested in?CheersJase
Also, you do know this will give you a voltage but you may not pull current?
Wow! Thanks so much for the replies. So a wave is comprised of frequencies (harmonics) both above and below the fundamental frequency.
This is the Fourier Series concept. Note that it does NOT mean that the waveform IS physically a sum of these things.
I don't see why it isn't (assuming, of course, that the waveform is truly periodic and exists from time t = -infinity to time t = infinity). Either way, there's no need to confuse OP. For all intents and purposes, a truly periodic signal IS physically a sum of the harmonics found by computing the Fourier Series.
Because.... physically, the physical signal in the time domain is 'The time domain Signal'.... which ...in this case.... is a periodic 2-level waveform (when the input is held at a constant value that is). Not a bunch of sinusoids (plus a DC shift, if there is one).
Also, if you look at a PWM signal specifically, even though it is a "2-level waveform", it still is comprised of sinusoids.