Steve,

Here's a National Semi link listing several references on PLLs - http://www.national.com/appinfo/w...56,00.html

Signetics published a hardback "Linear Applications" book about 1974 or '75. The 565, 566, and 567 were described in that book, as well as a good bit of applied theory. If you can get your hands on the book via a university library or such, it would be worth the effort. In the past, I've referred to Gardner's "Phaselock Techniques" as well and found it quite useful.

Bruce