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Re: Software PLL (SPLL)

Started by Ron N. February 8, 2006
Mark wrote:

> A software PLL is based on an NCO and an NCO unlike a VCO has a minimum > step size so it can only achieve a number of discrete frequencies, i.e. > the output frequency is quantized.
Why do you say this? An NCO is, of course based on some digital number representation; but if you use IEEE doubles, the quantization error of the phase is much smaller than the thermal noise of any analog oscillator, maybe even smaller than the quantum limits physics allows any analog VCO. IMHO. YMMV. -- rhn A.T nicholson d.0.t C-o-M