Circuit arrangement for frequency modulation has voltage controlled oscillator with varactor diode, which is controlled by control signal and capacitance of varactor diode depends on control signal

摘要

The circuit arrangement has a voltage controlled oscillator with a varactor diode, which is controlled by a control signal (UA) and a capacitance of the varactor diode depends on the control signal. A modulation device (101) of the voltage-controlled oscillator generates a modulation signal (UM) for the frequency modulation and a control device (100) generates the control signal and the modulation signal such that a linear connection is produced between the modulation signal and the capacitance of the varactor diode.