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:
Nov. 06, 2001
Filed:
Jun. 13, 2000
Applicant:
Inventors:
Jean-Marc Mourant, Groton, MA (US);
Daniel Shkap, Cambridge, MA (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03B 5/36 ;
U.S. Cl.
CPC ...
H03B 5/36 ;
Abstract
An oscillator circuit having improved long term and short term phase stability. A source follower provides a signal to a bipolar transistor. The bipolar transistor is fed with a current from a current mirror which may be selectively controlled. A piezoelectric crystal and a high resistance element are connected in parallel from the collector of the bipolar transistor to the input of the source follower. The drive voltage to the piezoelectric crystal is controlled by the current mirror to improve long term frequency stability.