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:
Feb. 04, 1986
Filed:
Mar. 21, 1984
Takahisa Emori, Kanagawa, JP;
Masafumi Kikuchi, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A frequency modulating circuit for modulating a carrier signal by a modulating signal is disclosed which includes a band-pass filter of biquad type having a first integrating circuit and a second integrating circuit, an output of the first integrating circuit being supplied to an input terminal of the second integrating circuit and an output of the second integrating circuit being supplied to an input terminal of the first integrating circuit and a second input terminal of the second integrating circuit, and a limiting amplifier circuit supplied with the output signal of the band-pass filter and the output thereof being positively fed back to the band-pass filter. In this case, the modulating signal is supplied to the first and second integrating circuits such that the center frequency of the band-pass filter is linearly controlled by the modulating signal whereby a frequency modulated signal modulated by the modulating signal is led out of the output terminal of the second integrating circuit.