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. 28, 1981
Filed:
Jun. 04, 1979
Eiichi Ishii, Tokyo, JP;
Nippon Electric Co., Ltd., Tokyo, JP;
Abstract
An FM demodulator circuit particularly suited for construction as an integrated circuit is disclosed. Circuitry which may also serve the function of an intermediate frequency amplifier and limiter shapes the input FM signal into two rectangular waves having opposite phases which are applied to the bases of first and second transistors. First and second constant current sources supply substantially constant currents to the emitters of the first and second transistors, respectively, and a capacitive element is connected between the emitters of the first and second transistors. An adder circuit adds the collector outputs of the first and second transistors, and the added output is supplied to a low-pass filter to derive an analog output.