A 1.8-V 3.6-mW 2.4-GHz Fully Integrated CMOS Frequency Synthesizer for the IEEE 802.15.4

This paper presents a low power 2.4-GHz fully integrated 1 MHz resolution IEEE 802.15.4 frequency synthesizer designed using 0.18um CMOS technology. An integer-N fully programmable divider employs a novel Truesingle-phase-clock (TSPC) 47/48 prescaler and a 6 bit P and S counters to provide the 1 MHz output with nearly 45% duty cycle. The PLL uses a series quadrature voltage controlled oscillator (S-QVCO) to generate quadrature signals. The PLL consumes 3.6 mW of power at 1.8 V supply with the fully programmable divider consuming only 600 uW. The S-QVCO consumes 2.8 mW of power with a phase noise of -122dBc/Hz at 1 MHz offset.