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:
May. 30, 1989
Filed:
Sep. 08, 1987
Siemens Aktiengesellschaft, Berlin and Munich, DE;
Abstract
In addition to a filter phase comparator, an integrator, a first filter and a voltage-controlled oscillator of relatively low stability and having a wide pull-in range, a circuit arrangement for generating a clock signal comprises a frequency generator of high stability having a narrow pull-in range, a second phase comparator and second and third filters. The first phase comparator is supplied with the reference frequency and the clock signal emitted by the voltage-controlled oscillator. The second phase comparator is supplied with the clock signal and a normal frequency generated by a normal frequency generator. In the event of the failure of the reference frequency or the overshooting of predetermined phase difference values, a regulating circuit formed by the second phase comparator, the second filter, the third filter and the voltage-controlled oscillator is closed.