In this paper, a new high dynamic range Digitally-Controlled Oscillator (DCO) for All-DPLL systems is proposed. The proposed DCO is based on using a ΔΣ modulator as a Digital-to-Analog converter. Using ΔΣ DAC can provide a very high resolution (18-bit) control on the DCO. The ΔΣ DAC output is a 2-level pulse signal that needs to be filtered for cancelling the out of band shaped noise. The used ΔΣ modulator is a 4th order MASH ΔΣ modulator working with the OSR of 128 and the sampling frequency of 450MHz. the proposed DCO is used in a PLL to synthesize the frequency in the range of 1700MHz to 1800MHz for GSM-1800 application. The achieved phase noise for this PLL based synthesizer in whole the range is -115 dBc/Hz at the offset frequency of 500 kHz. The designed ADPLL including the DCO is simulated in ADS with 0.18µm CMOS technology.
Jafarzade,S. and Jannesari,A. (2012). A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems. The Modares Journal of Electrical Engineering, 12(2), 16-21.
MLA
Jafarzade,S. , and Jannesari,A. . "A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems", The Modares Journal of Electrical Engineering, 12, 2, 2012, 16-21.
HARVARD
Jafarzade,S.,Jannesari,A. (2012). 'A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems', The Modares Journal of Electrical Engineering, 12(2), pp. 16-21.
CHICAGO
S. Jafarzade and A. Jannesari, "A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems," The Modares Journal of Electrical Engineering, 12 2 (2012): 16-21,
VANCOUVER
Jafarzade,S.,Jannesari,A. A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems. The Modares Journal of Electrical Engineering, 2012; 12(2): 16-21.
The Modares Journal of Electrical Engineering