Title :
Mixed-mode automatic tuning scheme for high-Q continuous-time filters
Author :
Karsilayan, A.I. ; Schaumann, R.
Author_Institution :
Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA
fDate :
2/1/2000 12:00:00 AM
Abstract :
An automatic tuning scheme using envelope detectors and simple mixed-mode circuitry is discussed. The method is developed especially for filters with large Q values and can be used at very high operating frequencies. The circuit was designed in a 1.2 μm CMOS process with a 3 V single supply voltage. As a demonstration filter, a second-order g m-C bandpass section is used, but the method can also be applied to lowpass and highpass sections. The measured frequency tuning error is less than 0.3% for filters with Q>80 operating in the range of 105 MHz-120 MHz
Keywords :
CMOS integrated circuits; Q-factor; VHF filters; band-pass filters; circuit tuning; continuous time filters; high-pass filters; low-pass filters; mixed analogue-digital integrated circuits; transfer functions; 1.2 micron; 105 to 120 MHz; 3 V; CMOS process; envelope detectors; high-Q continuous-time filters; highpass sections; lowpass sections; mixed-mode automatic tuning scheme; mixed-mode circuitry; second-order gm-C bandpass section;
Journal_Title :
Circuits, Devices and Systems, IEE Proceedings -
DOI :
10.1049/ip-cds:20000054
