A low-area switched-resistor loop-filter technique for fractional-N synthesizers applied to a MEMS-based programmable oscillator

Author

Perrott, M.H. ; Pamarti, Sudhakar ; Hoffman, E. ; Lee, F.S. ; Mukherjee, Sayan ; Lee, Chi-Kwan ; Tsinker, V. ; Perumal, Senni ; Soto, B. ; Arumugam, Niveditha ; Garlepp, B.W.

Author_Institution

SiTime, Sunnyvale, CA, USA

fYear

2010

fDate

7-11 Feb. 2010

Firstpage

244

Lastpage

245

Abstract

A fractional-N synthesizer is used in a programmable 1 to 115 MHz MEMS oscillator. A high gain phase detector lowers the impact of loop filter noise, and a switched-resistor loop filter avoids a charge pump and boosts effective resistance to save area. The entire synthesizer with LC-VCO occupies 0.31 mm² in 0.18 Â¿m CMOS. Chip consumption is 3.7 mA drawn from a 3.3 V supply for a 20 MHz output with no load.

Keywords

CMOS integrated circuits; frequency synthesizers; voltage-controlled oscillators; CMOS; MEMS-based programmable oscillator; current 3.7 mA; fractional-N synthesizers; frequency 1 MHz to 115 MHz; loop filter noise; low-area switched-resistor loop-filter technique; phase detector; size 0.18 mum; switched-resistor loop filter; voltage 3.3 V; Filters; Frequency conversion; Frequency synthesizers; Micromechanical devices; Phase locked loops; Phase noise; Resistors; Switches; Temperature sensors; Voltage-controlled oscillators;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Circuits Conference Digest of Technical Papers (ISSCC), 2010 IEEE International

Conference_Location

San Francisco, CA

ISSN

0193-6530

Print_ISBN

978-1-4244-6033-5

Type

conf

DOI

10.1109/ISSCC.2010.5433937

Filename

5433937