First error: Use much lower frequency signals than you use in your graphical example. I know it makes much more work but the higher one is definitely too close to the Nyquist freguency.
Second: No amplifier (independant of working principle) ever amplifies separate signals. It always amplifies a signal that is a sum of signals. So you would have to add your signals together first before you apply the PWM modulation.
If you want to separate summed Signals later on you must use a crossover of some sort.
Regards
Charles
Second: No amplifier (independant of working principle) ever amplifies separate signals. It always amplifies a signal that is a sum of signals. So you would have to add your signals together first before you apply the PWM modulation.
If you want to separate summed Signals later on you must use a crossover of some sort.
Regards
Charles
Hi,
One trw wave fixed at pin,other trw shift left to right and comparator not change duty cicle?....good!
what is "Audio information"? sorry...if apply audio signal ,(pwm contains the audio information), if you apply other type of signal,it contains other. eg. PWM can turn-on a fuel injector. Pulse /Time,(decides the change the quantity to be injected).In this case is not simple,other pwm segments first pwm).etc,etc.
Regards
Hi,
I put a low frequency only for see on oscilloscope the two signal on pwm.
Second: Nobody said it's output there are two separate signals.
this is obvious.
the question was: what happens by putting multiple signals at the comparator?
I responded with a simple example.
but in the normal work of an amplifier, the signal input (audio envelope) are many simultaneously with dynamic characteristics much different and complex, many of them non-sinusoidal.
For this reason, the premiere feature of a good amplifier should be speed. this, regardless of bandwidth.
Hi,
Pafi ... I am sure that you do not offend, I played (joke) a bit with you to see how time it takes to see that two triangle does not change pwm. eh, eh, eh!
is real, that I developed MXD contains two high frequency signals (not two TRW use). it is self-oscillating if you remember.
ok, the pic with two 100 Hz & 20 Hz signals is correct.
Regards
I think I understand your questions as much as it's possible, but your questions are basically wrong. You should think other way. Forget the wrong questions, and try to think the way our fathers (Fourier, Nyquist, Shannon, etc...) did!
You didn't answer to my question wether you know fourier transformation (etc...) or not. If you haven't heard about them, then you should learn the basics first. Or at least keep my advice and think it over with quasy-DC signals!
1.: A comparator has only 2 inputs! Forget 2 signals, there can be only one modulating signal (and one carrier = triangle), which possibly made by summing 2 or 3 or infinite other signals, but this is absolutely not important, only the one (the sum of all) signal counts. It can be any kind of signal, as long as it is a: "small" b: "band limited".
2.: As you know there is 1 PWM signal. Then what should the FET differentiate between?
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