Technological Scaling and Minimization of 1/fNoise in SiGe HBTs Coupled Mode N-Push Oscillators/VCOs

This paper investigates the impact of technological scaling and minimization of flicker (1/f) noise on SiGe HBTs in coupled mode N-push oscillator/VCO configuration, which have recently emerged as a strong contender for RF and mixed-signal applications. 1/f noise in SiGe HBTs is sensitive with technological scaling and upconverted in coupled mode oscillators due to the presence of asymmetrical output from their subsequent N oscillator subcircuits that forms N-push configuration. Improving the symmetry of the coupled mode N-push topology develops a method of minimizing the 1/f noise up-conversion and phase noise in the scaled device. The experimental result shows 10-15 dB improvement in the noise performances for symmetrical coupled mode VCO @ 10 kHz offset from the carrier frequency 8000 MHz in comparison to the asymmetrical version of the coupled mode scaled device (Infineon BFP 620)