4-GHz Fully Monolithic SiGe HBT QVCO Using Superharmonic Coupling Topology

This paper demonstrates a 4-GHz monolithic SiGe heterojunction bipolar transistor (HBT) quadrature voltage controlled oscillator (QVCO) using superharmonic coupling topology. The quadrature VCO at 4.17 GHz has phase noise of -116 dBc/Hz at 1MHz offset frequency, output power of -6 dBm and the figure of merit (FOM) -179 dBc/Hz. The core current consumption is 3.2 mA at 3V supply voltage. The die size is about 1.4 mm times 1.2 mm