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. 18, 1999
Filed:
May. 21, 1997
Richard R Rasmussen, Fremont, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A current controlled oscillator circuit comprising a 'variable-ratio current mirror', for providing a variable output current that varies in response to process. The 'variable-ratio current mirror' having a reference MOS transistor and a mirrored MOS transistor, and the reference MOS transistor has a greater predetermined channel length than the channel length of the mirrored MOS transistor. A second current mirror is coupled to the 'variable-ratio current mirror' to provide a control current that decreases in response to an increase in the variable output current of the 'variable-ratio current mirror.' A multi-stage ring oscillator having a plurality of series-connected inverter stages is responsive to the control current of said second current mirror for controlling the frequency of oscillation of said multi-stage ring oscillator.