Title: Fm signal oscillation circuit and modulation level correcting method
Application Number: 01121849 Application Date: 2001.06.29
Publication Number: 1339872 Publication Date: 2002.03.13
Approval Pub. Date: 2004.09.22 Granted Pub. Date: 2004.09.22
International Classifi-cation: H03C3/00;H03C3/22
Applicant(s) Name: Toshiba Corp. Address:
Inventor(s) Name: Eida Minoru
Attorney & Agent: wang yonggang
Abstract:
    An FM signal oscillator circuit includes a resonator having a graded- or abrupt-junction variable capacitance diode that is producible through standard IC manufacturing processes but causes an inconstant modulation level. Namely, to maintain a constant modulation level without regard to oscillation frequencies that change depending on a control voltage applied to the variable capacitance diode, the FM signal oscillator circuit employs a variable gain amplifier whose gain changes in response to the control voltage. The superimposed signal is applied to the variable capacitance diode, and a driver of the FM signal oscillator circuit provides an FM signal whose modulation level is constant irrespective of the control voltage that may vary.
Time: 10