Frequency Generation and Control with Self-Referenced CMOS Oscillators
Developments in the field of frequency generation and control have enabled a myriad of modern technologies ranging from wireless communications to synchronous computing. These technologies rely on precise frequency generation and control to perform functions including transmitting and receiving signals within specific frequency bands as well as timing data properly in a microprocessor.
Several frequency generation and control technologies exist, though none as ubiquitous as the piezoelectric quartz crystal oscillator (XO) and its derivatives. Jacques and Pierre Curie discovered piezoelectricity in the 1880s. Yet it was not until 1917 that Alexander M. Nicholson invented and demonstrated the first crystal-controlled oscillator using a piece of Rochelle salt. In 1921, Walter Guyton Cady developed the first quartz crystal oscillator. Since then, the field of frequency control grew rapidly, particularly due to the development of communication systems during World War II. In 1946, the first Frequency Control Symposium was held and it was within this forum that several significant advances in the field were reported including the consistent improvement in the performance of quartz XOs .
Since these origins, and with the explosive growth of the integrated circuit through the 1980s until today, several ...