Re: PLL Basics

On Feb 13, 2:30 pm, Jerry Avins <j...@xxxxxxxx> wrote:
Muzaffer Kal wrote:
On Fri, 13 Feb 2009 11:36:50 -0500, Jerry Avins <j...@xxxxxxxx> wrote:

Of course filters are used in a PLL implementation. That doesn't mean a
PLL is a filter, any more it is a VCO.

I'm curious as to how you make the distinction. What makes a PLL a
non-filter? It has an H(s), it takes a noisy periodic signal and
produces cleaned up, frequency shaped version of it. How is that
qualitatively different from an RC filter?

It's also a signal generator, no? The OP asked a a simple,question that
(it seemed to me) embodied a misconception that I tried to dispel. To
answer your question, a simple RC filter isn't bandpass.

Jerry
--
Engineering is the art of making what you want from things you can get.
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Furthermore, a PLL produces an output signal when the input is zero.
Is that different enough?

John
.

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