A 2.5GHz Series Resonance BAW Oscillator in a 130-nm BiCMOS process with 1kHz-offset Phase Noise <-98dBc/Hz and FOM >208dB

A 2.5GHz series resonance oscillator in an in-house 3rd generation 130-nm BiCMOS process is proposed. The oscillator uses an indigenous Bulk Acoustic Wave (BAW) resonator as the oscillating element and is mounted on top of the silicon die and co-packaged in a standard plastic mold compound. The oscillator can be driven in a high-FOM very low phase-noise mode with FOM >211dB or a high performance ultra-low phase-noise mode with a close-in phase noise better than -98dBc/Hz at 1kHz offset and FOM >208dB, with a 12kHz-20MHz integrated jitter <7fs.