A Class-D CMOS DCO with an on-chip LDO
Author
Summary, in English
This paper presents the co-design of a class-D digitally-controlled oscillator (DCO) and a low-dropout voltage regulator (LDO) generating the supply voltage for the DCO. Despite the high intrinsic supply pushing of the class-D oscillator topology, the LDO noise has only a very marginal impact on the DCO phase noise. The class-D DCO and LDO have been integrated in a 65nm CMOS process without any thick top metal layer. The oscillation frequency is tunable between 3.0 GHz and 4.3 GHz, for a tuning range of 36%, with a fine frequency step below 3 kHz and a fine frequency range of 10MHz (both measured at 3 GHz). Drawing 9.0mA from 0.4V (corresponding to an unregulated supply voltage of 0.6 V), the phase noise is -145.5 dBc/Hz at a 10MHz offset from a 3.0 GHz carrier. The resulting FoM is 189.5 dBc/Hz, and varies less than 1 dB across the tuning range. The FoM increases to above 190 dBc/Hz when the regulated supply voltage is 0.5V.
Department/s
Publishing year
2014
Language
English
Pages
335-338
Publication/Series
Proceedings Of The 40th European Solid-State Circuit Conference (ESSCIRC 2014)
Document type
Conference paper
Publisher
IEEE - Institute of Electrical and Electronics Engineers Inc.
Topic
- Electrical Engineering, Electronic Engineering, Information Engineering
Keywords
- VCO
- DCO
- class-D
- low phase noise
- high efficiency
- CMOS
- low-voltage
- LDO
- voltage regulator
Conference name
European Solid State Circuits Conference (ESSCIRC), 2014
Conference date
2014-09-22 - 2014-09-26
Conference place
Venice, Italy
Status
Published
ISBN/ISSN/Other
- ISSN: 1930-8833