Title :
On designing linearly tunable high-Q OTA-C filters with low sensitivity
Author :
De Lima, Jader A. ; Alcaide, Fernando M.
Author_Institution :
Dept. of Electr. Eng., Univ. Estadual Paulista, Guaratingueta, Brazil
Abstract :
This paper discusses a design approach for a high-Q low-sensitivity OTA-C biquad bandpass section. An optimal relationship is established between transconductances defining the difference β - γ in the Q-factor denominator, setting the Q-sensitivity to tuning voltages around unity. A 30-MHz filter was designed based on a 0.35μm CMOS process and VDD=3.3V. A range of circuit simulation supports the theoretical analysis. Q-factor spans from 20.5 to 60, while ensuring filter stability along the tuning range. Although a triode-operating OTA is used, the procedure can be extended to other types on transconductor.
Keywords :
CMOS integrated circuits; Q-factor; band-pass filters; biquadratic filters; circuit simulation; circuit stability; circuit tuning; operational amplifiers; sensitivity analysis; 0.35 microns; 3.3 V; 30 MHz; CMOS process; OTA-C filters; Q-factor denominator; Q-sensitivity; biquad bandpass section; circuit simulation; filter stability; high-Q filter; linearly tunable filter; low-sensitivity filter; optimal relationship; theoretical analysis; transconductor; triode-operating OTA; tuning range; Band pass filters; Capacitance; Circuit optimization; Circuit simulation; Q factor; Transconductance; Transconductors; Tunable circuits and devices; Tuning; Voltage;
Conference_Titel :
Circuits and Systems, 2004. ISCAS '04. Proceedings of the 2004 International Symposium on
Print_ISBN :
0-7803-8251-X
DOI :
10.1109/ISCAS.2004.1328121
