The Research Of 2/3 Division Wide Locking Range Injection-Locked Frequency Dividers

As one of the highest circuits in modern communication systems, frequency dividers play an important role in determining the system’s speed and signal quality. Injection-Locked Frequency Dividers (ILFDs) are favored in many high frequency applications due to the characteristics of high speed, low power consumption and low noise. However, some instinct problems are still restraining the utilization such as model establishment, frequency division mode and noise. Therefore there is a need for deeper understanding of ILFDs’principles to obtain the meaningful results.To answer those problems, fresh analysis was firstly undertaken from the view of phase domain in the areas of models, locking range, nonlinearity, dynamic behaviors and phase noise. Besides, basic theories and some guidelines were also acquired for the ILFDs.Secondly, based on the theory conclusions, an ILFD was designed in this paper aiming to realize wide locking range and multi-modulus division. It included a tunable active inductance (TAI) constructing the resonance tank, different injection methods for variable division ratios and even harmonic reinforcements. Diversified simulations were carried out to complete the design and testify theories.Eventually, the ILFD design was fabricated in Chartered Semiconductor 0.35μm EEPROM CMOS technology which was tested to further prove the conclusions. It turned out that under 3.3V power supply, the results met the expectations to realize wide locking range in both modulus in which division of two reached a range of 28.9%(1.57GHz to 2.1GHz) and that of three committed a range of 11.4%(1.74GHz to 1.95GHz). Meanwhile problems of testaments and designs were also explained in the final part which would give some instructions for the future directions.