Chip package co-design of a heterogeneously integrated 2.45 GHz CMOS VCO using embedded passives in a silicon package

Phase Noise Performance of a Voltage Controlled Oscillator that determines spectral purity is dependent on the Quality Factor (Q) of the tank in LC Oscillators. On-chip inductors that are used to realize the LC tank have comparatively low quality factors and consume considerable die area. Here a Chip-Package Co-Design for a 2.45 GHz VCO is described using a high Q (∼30) inductor embedded in a silicon substrate. The heterogeneously integrated circuit has a phase noise of -110 dBc/Hz at a 100 kHz offset with power dissipation of 28 mW from a 2.5 V supply and has a tuning range of 6%. The resulting improvement in inductor coil quality factor, phase noise and area savings compared to a fully integrated VCO design is demonstrated.