A wide-band CMOS synthesizer for cable tuner applications

Abstract

A 1.8-V wide-band CMOS frequency synthesizer for cable tuner applications is designed and measured using a standard 0.18-μm CMOS process. The proposed frequency synthesizer uses only one wide band VCO to provide LO frequencies which saves chip area and power consumption. A ring oscillator with switched-capacitor arrays is employed to achieve a wide operating frequency range and low phase noise. The wide band VCO drives an integer-N phase locked loop with an on chip fourth order dual path loop filter which are fully integrated on a single chip.

The measured operating frequency range of the frequency synthesizer is 180 MHz to 648 MHz. The measured phase noise is -95 dBc/Hz and -110 dBc/Hz at frequency offsets of 10 kHz and 1 MHz respectively. The spur performance is less than -64 dBc at 6-MHz offset. The measured IQ phase mismatch is less than 0.1 degree, and the image rejection measured with on-chip mixers is more than 61dB. The synthesizer dissipates 40mW from a single 1.8-V supply. The core chip area is 2 mm².

Date of Award	2005
Original language	English
Awarding Institution	The Hong Kong University of Science and Technology