Abstract: According to one exemplary embodiment, a VCO core circuit is connected across a first node and a second node. The anode of a first varactor is connected to the first node while the anode of a second varactor is connected to the second node, and the cathode of the first varactor is tied to the cathode of the second varactor. A tuning voltage is also connected to the cathode of the first varactor and the cathode of the second varactor. The inductor is connected across the first node and the second node. A first and second bipolar transistors are configured as a differential pair. A first and second FETs are configured in a common-gate configuration. The drain of the first FET comprises a first output of the BiFET VCO circuit, while the drain of the second FET comprises a second output of the BiFET VCO circuit.