Title :
CMOS VCOs for frequency synthesis in wireless biotelemetry
Author :
Betancourt-Zamora, Rafael J. ; Lee, Thomas H.
Author_Institution :
Stanford Univ., CA, USA
Abstract :
A new phase noise model was used to optimize a differential ring VCO for minimum power consumption. We compare the phase noise performance of three buffer stages using clamped, symmetric and cross-coupled loads, respectively. We propose a cross-coupled buffer topology that achieves lower phase noise by exploiting symmetry. Measured phase noise for a 1.2 mW, 150 MHz VCO fabricated in 0.5 /spl mu/m CMOS is -103.9 dBc/Hz at 500 kHz offset, showing good agreement with the theory.
Keywords :
CMOS analogue integrated circuits; VHF oscillators; biomedical telemetry; frequency synthesizers; integrated circuit noise; low-power electronics; phase noise; radiotelemetry; voltage-controlled oscillators; 0.5 micron; 1.2 mW; 150 MHz; CMOS VCOs; buffer stages; clamped load; cross-coupled buffer topology; cross-coupled load; differential ring VCO; frequency synthesis; minimum power consumption; phase noise model; symmetric load; wireless biotelemetry;
Conference_Titel :
Low Power Electronics and Design, 1998. Proceedings. 1998 International Symposium on
Conference_Location :
Monterey, CA, USA
Print_ISBN :
1-58113-059-7
