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:
Apr. 27, 2004
Filed:
Oct. 29, 2002
Uday Dasgupta, Singapore, SG;
Institute of Microelectronics, Singapore, SG;
Abstract
A relaxation current controlled oscillator (CCO) is provided by forming an integrator out of a transconductance amplifier and a capacitor. The output of the integrator is fed to comparators which in turn feed a bistable circuit. The outputs of the bistable circuit control either the polarity of the input signals to the transconductance amplifier or the polarity of the input signals to the comparators. Switches, controlled by the bistable circuit, in turn control the polarity of the input signals. The feedback path created by the transconductance amplifier, comparators, flip-flops, and switches produces continuous oscillations. A DC current input adjusts the g of the transconductance amplifier allowing the oscillation frequency of the CCO to be adjusted. Several embodiments of CCOs are described which are fully compatible with PLLs with automatic time-constant or bandwidth tuning of a gm-C filter.