High-modulus Current-reused Injection-Locked Frequency Dividers (FDs) with an Odd-modulus Sub-FD

Abstract

This letter studies high-modulus LC injection-locked frequency dividers (ILFDs) designed with the current-reused technique, which uses two sub-circuits sharing the same dc current and device components. The current-reused ILFDs use one divide-by-3 ILFD and they include $\div 6, \div 9$ and $\div 10$ ILFDs. These circuits cannot be obtained by cascading even-modulus ILFDs. Since the supply current to one sub-ILFD is limited by the other sub-ILFD, the design of a sub-circuit is different from the design of the voltage-mode ILFD. The current-reused $\div 6$ ILFD was designed in the TSMC 0.18 $\mu \mathrm{m}$ BiCMOS process. It is based on a $\div 2$ LC p-core ILFD stacking on a $\div 3$ LC n-core capacitive cross-coupled ILFD. At the drain-source bias VDD of 1.6/1.2 V and at the incident power of 0dBm, the locking range is 3/2GHz (23.62/15.87%), from the incident frequency 11.2/11.6 GHz to 14.2/13.6 GHz. The core power consumption is 17. 47/6.312mW and the die area is $0.988 \times 1.0185 \mathrm{mm}^{2}$.