A 19GHz 0.5mW 0.35μm CMOS Frequency Divider with Shunt-Peaking Locking-Range Enhancement

H. Wu and A. Hajimiri

A frequency divider is an essential building block and one of the major sources of power dissipation in widely-used frequency synthesizers. As the output frequency of the synthesizer increases, the trade-off between the speed and power dissipation of dividers becomes more critical. Narrow-band injection-locked frequency dividers (ILFD) dissipate a fraction of the energy stored in the tank, which is determined by the quality factor, Q, of the resonator, in every cycle. Therefore, they have fundamentally lower power dissipation than wide-band dividers. Due to their narrow-band nature, ILFDs work in a limited frequency range (locking range). In this paper, shunt-peaking is used as an approach to increase the locking range and lower the power dissipation at higher frequencies.