Sun, 27 Jul 2008 07:51:38 BST CiteULike: dcastro's library [2022 articles] http://www.citeulike.org/user/dcastro/article/2776104 CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2776104 <i>Communications, IEEE Transactions on [legacy, pre - 1988], Vol. 25, No. 10. (1977), pp. 1210-1214.</i><br /><br />A phase-lock loop occasionally will take a long time to settle to equilibrium. Phase dwells at a large error for a prolonged interval. This phenomenon has been dubbed "hangup." The periodic nature of phase detectors is responsible for hangup, which occurs near the reverse-slope, unstable null. Restoring force is small in the vicinity of the reverse null, and noise causes the loop to equivocate about the null. Hangup is very troublesome when fast acquistion is needed with high reliability. One example is synchronization of digital communications. Hangups can be avoided if a large restoring force is applied for large phase errors and if equivocation is prevented. An implementation of an antihangup circuit is proposed. Hangup in Phase-Lock Loops F Gardner Communications, IEEE Transactions on [legacy, pre - 1988], Vol. 25, No. 10. (1977), pp. 1210-1214. 2008-05-09T15:16:18-00:00 1977 Communications, IEEE Transactions on [legacy, pre - 1988] 25 10 1210 1214 pll