The increasing demand for high-performance devices featuring compact, lighter-weight designs with low-power consumptionalso impacts quartz crystal oscillators used in metrological applications (time bases, sensors), telephony or navigation. Inthis context, we have developed an ASIC (Application Specific Integrated Circuit) in 0.35 μm SiGe BiCMOS technology(Austriamicrosystems®) supplied by 3.3 V (±10%) to realize a miniaturized quartz crystal oscillator operating in the 10 MHzto 100 MHz frequency range. The fabricated die hosts several RF cells in a 4 mm2 area, including a sustaining amplifier(Colpitts topology), a signal shaping circuit and an output buffer dedicated to a specific load (50 W or HCMOS). These cellsare biased by a fully integrated CMOS bandgap voltage reference. The die power consumption remains lower than 100 mWfor a targeted phase noise floor as low as −150 dBc/Hz at a 40 MHz carrier frequency. A thermal control loop has in additionbeen partially integrated to the ASIC, in order to reduce the quartz resonator thermal sensitivity as well as to extend thepotential application field of the developed die to oven applications (OCXO). The thermal control, that is strongly dependanton the mechanical design, has been designed and tested by using electrical analogy modeling on Spectre® simulator. Finallyour integrated circuit has been connected to a specific substrate using flip chip technology to realize a miniaturized quartzcrystal oscillator packaged on a TO-8 enclosure (Ø15.2 mm).
