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:
Oct. 24, 2017
Filed:
Dec. 01, 2016
Industrial Technology Research Institute, Hsinchu, TW;
INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE, Hsinchu, TW;
Abstract
A power amplifier circuit including a power transistor, a variable impedance circuit, first and second envelope detecting circuits is provided. The power transistor receives an input signal and outputs an output signal. The variable impedance circuit includes an impedance control transistor and a first filter capacitor. An equivalent impedance of the variable impedance circuit varies with the input signal. The impedance control transistor is coupled to the power transistor and receives a control voltage. The first filter capacitor is coupled between the impedance control transistor and ground. Both the first and the second envelope detecting circuits detect the input signal to dynamically control the equivalent impedance of the variable impedance circuit.