The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 25, 1995
Filed:
Jan. 21, 1994
Andrew M Harris, Phoenix, AZ (US);
Calcomp Inc., Anaheim, CA (US);
Abstract
A phase lock loop (PLL) circuit which includes an input for inputting an incoming signal which is to be tracked, a phase lock loop subcircuit, a phase state indicator subcircuit, and a synchronized blanking window generator. These elements create a phase lock loop circuit capable of producing a stable output which closely tracks the incoming signal, even when the incoming signal shifts in phase by 180 degrees. The phase state indicator subcircuit detects a phase reversal in the incoming signal and outputs a signal indication such. This indicating signal is used by the phase lock loop subcircuit to produce a stable reference signal tracking the incoming signal most of the time. However, during a short period of time between the inversion of the incoming signal and the output of the indicating signal by the phase state indicator subcircuit, the synchronized blanking window generator provides a signal to the phase lock loop subcircuit which is used to stabilize the reference signal.