Title :
A 2.5 GHz CMOS fully-integrated ΔΣ-controlled fractional-N frequency synthesizer
Author :
Dehghani, Rasoul
Author_Institution :
Dept. of Electr. Eng., Sharif Univ. of Technol., Tehran, Iran
Abstract :
The design of a fully-integrated ΔΣ-controlled fractional-N frequency synthesizer is described. Using a dual modulus 64/72 prescaler based on injection locking technique and a novel third order digital ΔΣ modulator, we achieved an extremely low power synthesizer in 2.5 GHz band. Total power dissipation of the frequency synthesizer is less than 6 mW at a 1.5 V supply. The loop bandwidth is optimized to achieve a -123 dBc/Hz phase noise at 3 MHz offset frequency. The locking time of the loop is less than 30 μs.
Keywords :
CMOS integrated circuits; delta-sigma modulation; frequency synthesizers; integrated circuit noise; prescalers; voltage-controlled oscillators; 1.5 V; 2.5 GHz; 3 MHz; 6 mW; CMOS fully integrated ΔΣ synthesizer; digital ΔΣ modulator; fractional-N frequency synthesizer; injection locking technique; locking time; loop bandwidth; low power synthesizer; offset frequency; power dissipation; Frequency synthesizers; Logic; MOSFETs; Noise figure; Phase noise; Quantization; Tail; Transfer functions; Very large scale integration; Voltage-controlled oscillators;
Conference_Titel :
VLSI Design, 2004. Proceedings. 17th International Conference on
Print_ISBN :
0-7695-2072-3
DOI :
10.1109/ICVD.2004.1260919
