Electronic tuning system

A radio receiver comprising:

• a voltage controlled oscillator for generating a local frequency signal having a frequency in accordance with a predetermined control voltage;
• a mixer coupled to the voltage controlled oscillator for mixing a received signal with a local frequency signal to generate a mixed frequency signal;
• an intermediate frequency filter coupled to the mixer for filtering the mixed frequency signal to generate an intermediate frequency signal;
• a detector circuit coupled to the intermediate frequency filter for demodulating the intermediate frequency signal to an audio signal;
• an electronic tuner coupled to the voltage controlled oscillator for adjusting the predetermined control voltage to tune the local frequency signal to radio waves on an arbitrary channel in accordance with channel selection information;
• a booster circuit coupled to the voltage controlled oscillator for boosting a source voltage to generate a boosted voltage in order to ensure a predetermined control voltage, wherein the booster circuit includes,
• a coil coupled to a power source;
• a switching element coupled to the coil for periodically conducting a DC current flowing through the coil to a ground to change the DC current;
• a zener diode coupled to the coil for clamping an electromotive force induced in the coil in accordance with a change in the DC current flowing through the coil to a predetermined voltage;
• and
• a capacitor for smoothing the clamped voltage to generate a boosted voltage;
• and
• a non-volatile memory for storing the channel selection information in accordance with a predetermined write voltage, wherein the boosted voltage of the booster circuit is utilized as the predetermined write voltage, wherein the capacitor is coupled between the non-volatile memory and a node between the zener diode and the voltage controlled oscillator.