Title :
Stability of a continuous-time state variable filter with ORA-L and current amplifier integrators
Author :
Bakken, T. ; Choma, J., Jr.
Author_Institution :
Dept. of Electr. Eng. & Electrophys., Univ. of Southern California, Los Angeles, CA, USA
Abstract :
The stability of a continuous-time state variable filter is analyzed using the Routh-Hurwitz criterion. This criterion assesses stability by indicating the number of poles that lie in the right-half plane. The filter is examined separately with integrators implemented with an ORA-L and a current amplifier. Both amplifier types are characterized by a dominant-pole frequency response, and the stability of each implementation is compared. HSPICE simulations confirm the theoretical analyses, which indicate that the bandwidth of the ORAs and current amplifiers must be much larger than the desired frequency of operation to ensure stability. Since the analyses assume a dominant-pole response, all higher-order poles of the actual amplifier must also be much greater than the unity-gain frequency to minimize excess phase
Keywords :
Routh methods; SPICE; circuit analysis computing; circuit stability; continuous time filters; digital simulation; frequency response; integrating circuits; poles and zeros; HSPICE simulations; ORA-L; Routh-Hurwitz criterion; continuous-time state variable filter; current amplifier integrators; dominant-pole frequency response; excess phase; higher-order poles; poles; stability criterion; Active filters; Analytical models; Band pass filters; Bandwidth; Circuit stability; Frequency response; Operational amplifiers; Stability analysis; Stability criteria; Voltage;
Conference_Titel :
Circuits and Systems, 1998. ISCAS '98. Proceedings of the 1998 IEEE International Symposium on
Conference_Location :
Monterey, CA
Print_ISBN :
0-7803-4455-3
DOI :
10.1109/ISCAS.1998.704094
