3.1 An Integrated BAW Oscillator with <±30ppm Frequency Stability Over Temperature, Package Stress, and Aging Suitable for High-Volume Production

Wireless sensor nodes with low power and small form factor are desirable for emerging IoT applications. These nodes usually consist of a processor, memory, radio, sensors, battery, and two quartz crystals: one at 32kHz to synchronize data transmission and the other in the MHz range to synthesize RF signals. SoC integration of the memory, processor, and radio is common; however the MHz crystal remains external, which makes up a significant portion of the entire wireless node size.