Talk:William F. Egan

Latest comment: 3 years ago by North8000 in topic Feedback from New Page Review process

Years edit

 https://magazine.scu.edu/classnote/william-f-egan/

Additional refs edit

In 1981, describing high-order loops, William Egan conjectured that the addition of the zero pole to the loop filter's transfer function causes the hold-in and pull-in (acquisition) ranges to be theoretically infinite , i.e. that the hold-in and pull-in ranges of type 2 PLL are theoretically infinite: "The most common additional singularities are a low-frequency zero and a very-low-frequency pole (Fig.7.5d), essentially at zero frequency in many cases (see Fig. 7.5c), so that the hold-in range and acquisition range became theoretically infinite. That is, for the simplified model, they are infinite, although circuit limitations, such as finite VCO tuning range, will cause them to be finite".[1]: 176  In his book, published in 1998[2]: 192 , he wrote that "We might also say that significant deviations occur when \Omega_{PI} is approached for the lag-lead filter; this is to be expected since the type 2 loops have infinite \Omega_{PI}." Later similar statement was formulated in various articles and books.

In 1986, Egan's conjecture (without ref to his original work) was published in Aguirre, S., Brown, D.H., and Hurd, W.J. (1986). Phase Lock Acquisition for Sampled Data PLL's Using the Sweep Technique. TDA Progress Report 4, 86, 95-102, page 96: "an analog PLL with a type II loop has an infinite pull-in range".

In Bandwidth Variation, A Fully Differential Phase-Locked Loop With Reduced Loop, 2011 the statement of Egan's conjecture is provided on page 22 without ref to Egan.

Amr M. Fahim noted in his book[3]: 6  that "in order to have an infinite capture range, an active filter must be used for the loop filter".

Similar statement can be found in (2005) Phase-Locked Loop Fundamentals. In: Clock Generators for SOC Processors. Springer, Boston, MA on page 6 (there is ref to Egan's book 1990 - see ref 13).

Since additional refs have been provided, thus I removed the BLP primary sources template.

nk (talk) 09:37, 4 June 2020 (UTC)Reply

References

  1. ^ Egan, William F. (1981). Frequency synthesis by phase lock (1st ed.). New York: John Wiley & Sons.
  2. ^ Egan, William F. (1998). Phase-Lock Basics (1st ed.). New York: John Wiley & Sons.
  3. ^ Fahim, Amr M. (2005). Clock Generators for SOC Processors: Circuits and Architecture. Boston-Dordrecht-London: Kluwer Academic Publishers.


Additional explanations edit

I suggest to add the corresponding figure: Baseband model of type 2 analog PLLs.

 
Baseband model of type 2 analog PLLs

Milich64 (talk) 15:44, 22 June 2020 (UTC)Reply

Feedback from New Page Review process edit

I left the following feedback for the creator/future reviewers while reviewing this article: Good start!.

North8000 (talk) 01:19, 30 June 2020 (UTC)Reply