Patent ID: 8786376

Claim:
A voltage controlled oscillator, comprising: a transistor; a tank circuit interconnecting said transistor in feedback, said tank circuit including an inductor having a value L, interconnected with first and second variable capacitors, having values C VAR1 and C VAR2 , and a fixed capacitor C FIXED , to cause oscillation of said oscillator at a controlled frequency f osc = ( 2 ⁢ π ) - 1 ⁢ ( L ⁢ { C VAR ⁢ ⁢ 2 + C FIXED ⁢ C VAR ⁢ ⁢ 1 C FIXED + C VAR ⁢ ⁢ 1 } ) - 1 / 2 wherein adjustment of C VAR1 and C VAR2 control tuning of said oscillator, wherein said first variable capacitor and said fixed capacitor form a voltage divider, and wherein a node in said voltage divider interconnecting said first variable capacitor and said fixed capacitor provides feedback to said transistor; wherein said first variable capacitor C VAR1 is formed as a bank of parallel variable capacitors, the capacitance of each of which may be selectively adjusted by a control signal; wherein each capacitor of said bank of parallel variable capacitors is formed as two back-to-back connected MOS varactors.