Title :
Low-voltage current-mode filters
Author :
Galvez-Durand, F.
Author_Institution :
PPE Div., CERN, Geneva
Abstract :
A novel analogue continuous-time current-mode filter synthesis technique is proposed based on a transformed set of state-equations that allow the utilization of only current-mode linear lossy-integrators, implemented using standard current mirrors; also a novel current-mode gyrator is introduced. The technique has been successfully used for synthesizing a low-voltage 5th order 1 MHz lowpass Chebyshev filter from a passive doubly loaded ladder prototype. SPICE simulations using CMOS standard process level 2 parameters have shown this filter performs well, exhibiting a THD less than 1% at 1 MHz for a 40 mV output (1 μA input current) while the bias current per transistor is 10 μA. Also, a Monte Carlo analysis has shown this filter preserves the low sensitivity inherent to the passive ladder prototype. Only 22 transistors driving signals were needed. The circuit has been fed with ±1.5 V power supplies
Keywords :
CMOS analogue integrated circuits; Chebyshev filters; Monte Carlo methods; continuous time filters; gyrators; integrating circuits; linear network synthesis; low-pass filters; -1.5 V; 1 MHz; 1 muA; 1.5 V; 40 mV; CMOS implementation; LV current-mode filters; Monte Carlo analysis; SPICE simulations; THD; active filters; continuous-time filter synthesis technique; current-mode gyrator; linear lossy-integrators; low-voltage 5th order filter; lowpass Chebyshev filter; passive doubly loaded ladder prototype; standard current mirrors; state-equations; CMOS process; Chebyshev approximation; Circuits; Gyrators; Mirrors; Monte Carlo methods; Nonlinear filters; Passive filters; Prototypes; SPICE;
Conference_Titel :
Circuits and Systems, 1996., IEEE 39th Midwest symposium on
Conference_Location :
Ames, IA
Print_ISBN :
0-7803-3636-4
DOI :
10.1109/MWSCAS.1996.588082
