The Low Power and Wide Tuning Range Advantages of Armstrong VCOs in 180 nm Si-Ge HBT Technology

Abstract—When implemented in Si-Ge HBT technology, the differential Colpitts LC Voltage-Controlled Oscillator (VCO) can deliver low close-in phase noise by virtue of its low flicker noise corner frequency. The Armstrong... [ view full abstract ]

Abstract—When implemented in Si-Ge HBT technology, the
differential Colpitts LC Voltage-Controlled Oscillator (VCO) can
deliver low close-in phase noise by virtue of its low flicker noise
corner frequency. The Armstrong topology reuses bias current
and therefore should be more power-efficient than Colpitts.
By comparing differential Colpitts and Armstrong architectures
side-by-side, this paper shows that the Armstrong topology can
deliver similar noise performance with an order of magnitude
lower power consumption. This gives the Armstrong an 11 dB
advantage in terms of Figure of Merit (FoM).