Design of area-efficient GHz range current mode frequency synthesizer using standard CMOS technology

Dan-Dan Zheng – Yu-Bin Li – Chang-Qi Wang – Kai Huang – Xiao-Peng Yu

   In this paper, an area and power efficient current mode frequency synthesizer for system-on-chip (SoC) is proposed. A current-mode transformer loop filter suitable for low supply voltage is implemented to remove the need of a large capacitor in the loop filter, and a current controlled oscillator with additional voltage based frequency tuning mechanism is designed with an active inductor. The proposed design is further integrated with a fully programmable frequency divider to maintain a good balance among output frequency operating range, power consumption as well as silicon area. A test chip is implemented in a standard 0.13 mm CMOS technology, measurement result demonstrates that the proposed design has a working range from 916M Hz to 1.1 GHz and occupies a silicon area of 0.25 mm² while consuming 8.4 mW from a 1.2 V supply.

Keywords: frequency-locked loop, CMOS, integrated circuit, active inductor

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