Patent ID: 7936224

Claim:
A voltage controlled oscillator, comprising: a tunable first capacitor having a first end and a second end; a first transformer winding having a first end directly connected to the first end of the first capacitor, a second end directly connected to the second end of the first capacitor and a first center tap arranged to receive a first voltage, wherein the first and second ends of the first capacitor are not directly connected to the first center tap of the first transformer winding; a second transformer winding coupled to the first transformer winding, wherein an inductance value of the second transformer winding is a predetermined number of times an inductance value of the first transformer winding; a negative resistance element directly connected to both ends of the second transformer winding to provide a negative resistance; a second capacitor having a first end and a second end, wherein the second transformer winding comprises a first end directly connected to the first end of the second capacitor, a second end directly connected to the second end of the second capacitor and a second center tap arranged to receive a second voltage, wherein the first voltage is equal to the second voltage.