Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6879188 | AEU - International Journal of Electronics and Communications | 2018 | 34 Pages |
Abstract
Based on the analysis of the limitations of traditional compensation methods for analog temperature compensated crystal oscillators (ATCXOs), a new compensation algorithm and compensation network for ATCXOs are proposed in this paper. According to the frequency-temperature characteristics of AT-cut quartz crystals, the gain-temperature characteristics of voltage control crystal oscillators (VCXOs) are firstly derived and approximated by cubic functions. To improve the gain-temperature characteristics of ATCXOs, a quartic compensation algorithm and network are derived using curve fitting technique. A proposed design is implemented using 0.40â¯Âµm BCD process. Chip measurement results show that the frequency-temperature stability is within ±0.45â¯ppm over a temperature range of â40â¯Â°C to 85â¯Â°C. The phase noise levels are â87â¯dBc/Hz, â113â¯dBc/Hz, â137â¯dBc/Hz, and â152â¯dBc/Hz at 10â¯Hz, 100â¯Hz, 1â¯kHz, and 10â¯kHz frequency offset of 26â¯MHz AT-cut crystal, respectively. Compared with existing ATCXO designs in the literature, our proposed ATCXO chip improves the frequency-temperature stability by at least 55%, while maintaining a similarly low level of phase noise.
Keywords
Related Topics
Physical Sciences and Engineering
Computer Science
Computer Networks and Communications
Authors
Huachao Xu, Yuanzhi Zhang, Ke Liang, Chao Lu, Guofeng Li,