Volume 12, Issue 2 (2012)
MJEE 2012, 12(2): 16-21 |
Back to browse issues page
Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
Jafarzade S, Jannesari A. A High Dynamic Range Digitally-Controlled Oscillator (DCO) for All-Digital PLL Systems. MJEE 2012; 12 (2) :16-21
URL: http://mjee.modares.ac.ir/article-17-533-en.html
URL: http://mjee.modares.ac.ir/article-17-533-en.html
1- Tarbiat Modares University, samira.
2- Tarbiat Modares University,
2- Tarbiat Modares University,
Abstract: (4784 Views)
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.
Received: 2004/07/4 | Accepted: 2015/03/1 | Published: 2015/11/22
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |