Title :
A digitally controlled 2.4-GHz oscillator in 65-nm CMOS
Author :
Xu, Liangge ; Lindfors, Saska
Author_Institution :
Helsinki Univ. of Technol., Helsinki
Abstract :
This paper presents a 2.4-GHz digitally controlled oscillator (DCO). The circuit is designed using a 65-nm six-metal CMOS technology with an operating voltage of 1.2 V. The DCO comprises an LC oscillator core and the digital interface logic. It has a frequency range of about 200 MHz covering the 2.4-GHz ISM band, with around 5 MHz available for frequency modulation. Its frequency quantization step is approximately 20 kHz, with a digital SigmaDelta-modulator used to allow a 5-bit fractional digital control and provide an effective frequency resolution better than 1 kHz. Its free running oscillation phase noise is -125 dBc/Hz at 1 MHz frequency offset with 4.8 mA biasing current. The power consumption is adjustable from 1.8 mW to 12 mW.
Keywords :
CMOS integrated circuits; frequency modulation; integrated circuit design; integrated circuit noise; oscillators; phase noise; quantisation (signal); signal resolution; CMOS technology; LC oscillator; circuit design; current 4.8 mA; digital interface logic; digital modulator; digitally controlled oscillator; frequency 1 MHz; frequency 2.4 GHz; frequency modulation; frequency quantization; frequency resolution; phase noise; power 1.8 mW to 12 mW; power consumption; size 65 nm; voltage 1.2 V; CMOS digital integrated circuits; CMOS logic circuits; CMOS technology; Digital control; Digital-controlled oscillators; Frequency modulation; Logic design; Phase noise; Quantization; Voltage-controlled oscillators;
Conference_Titel :
Norchip, 2007
Conference_Location :
Aalborg
Print_ISBN :
978-1-4244-1516-8
Electronic_ISBN :
978-1-4244-1517-5
DOI :
10.1109/NORCHP.2007.4481047
