A 300 µmW 1.9GHz CMOS oscillator utilizing micromachined resonators

A low-power, low phase-noise 1.9GHz RF oscillator is presented. The oscillator utilizes a single thin-film bulk acoustic wave resonator and was implemented in a standard 0.18µm CMOS process. This paper addresses design issues involved in co-designing micromachined resonators with CMOS circuitry to realize ultra-low power RF transceiver components. The oscillator achieves a phase noise performance of -100dBc/Hz at 10kHz offset, -120dBc/Hz at 100kHz offset, and -140dBc/Hz at 1MHz offset. The start-up time of the oscillator is less than 1µS. The oscillator core consumes 300µA from a 1V supply.