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:
Jul. 29, 2003
Filed:
Jun. 26, 2000
David A. Newman, Tempe, AZ (US);
Benjamin R. Gilsdorf, Phoenix, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An envelope detector circuit for use in controlling a RF amplifier is provided. The envelope detector circuit includes a first semiconductor device having a first input port that receives a first input signal and a first output port that provides current to charge a capacitor in response to the first input signal. The envelope detector circuit additionally includes a first current drain coupled to the first semiconductor device and the capacitor, where the first current drain conducts current away from the capacitor. The envelope detector circuit further includes a second semiconductor device having a second input port that is set to a biasing voltage and a second output port that is coupled to the first output port of the first semiconductor device. A voltage level of the first output port is indicative of a level of an envelope of the first input signal when the voltage level remains above a threshold voltage equaling the biasing voltage minus a semiconductor voltage, and the voltage level otherwise does not fall below the threshold voltage.