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:
Aug. 17, 1999
Filed:
Jul. 14, 1998
Klaas J Lulofs, Drachten, NL;
Tjerk Bij De Leij, Drachten, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An RC oscillator having an oscillation frequency which is controllable by supplying a step voltage signal to a series arrangement of a capacitor and a resistor, the oscillation frequency being dependent on the time for the capacitor to be charged to a given voltage level. In order to vary the frequency, the amplitude of the supplied step voltage is varied instead of the resistance of the resistor via which the capacitor is charged. The amplitude variation can be provided, for example, by a potentiometer which acts as a voltage divider for the step voltage. The tolerance of the potentiometer in regard to its resistance value will not be relevant, because it is only the ratio between different portions thereof which is determinative. The step voltage, and consequently the oscillation frequency, will be proportional to the setting of the potentiometer regardless of the resistance tolerance thereof.