Title :
An accurate automatic tuning scheme for high-Q continuous-time bandpass filters based on amplitude comparison
Author :
Liu, Hengsheng ; Karsilayan, Aydin Ilker
Author_Institution :
Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA
Abstract :
A new automatic tuning scheme for continuous-time high-Q bandpass filters is presented. It is conducted by amplitude comparison at three frequencies generated by an on-chip frequency synthesizer. Theoretical analysis and experimental results are provided. Analysis shows the tuning method is suitable for bandpass filters with Q>10. A gm-C second-order filter is designed to demonstrate the proposed tuning scheme. The test chip is fabricated in AMI 0.5 μm process. The measured frequency tuning error is 0.25%, and Q-tuning error is 3% for a 200 MHz filter with a desired Q of 28.6.
Keywords :
CMOS integrated circuits; Q-factor; band-pass filters; circuit tuning; continuous time filters; frequency synthesizers; mixed analogue-digital integrated circuits; 0.5 micron; 150 to 210 MHz; 200 MHz; 3 V; 35 mW; AMI process; CMOS IC; active filters; automatic tuning scheme; clock generator; continuous-time filters; frequency divider; gm-C second-order filter; high-Q bandpass filters; on-chip frequency synthesizer; tuning method; Ambient intelligence; Band pass filters; Circuit optimization; Circuit testing; Detectors; Error correction; Frequency synthesizers; Gain control; Q factor; Tuning;
Journal_Title :
Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on
DOI :
10.1109/TCSII.2003.814802
