Gain-tuned programmable 2nd-order filters with VCVS

Based on the characteristic polynomial decomposition of 2nd-order active filters with voltage-controlled voltage sources (VCVS), filters with gain-tuned pole frequency/bandwidth/q-factor have been selected. Design procedures ensuring low errors of parameter setting have been outlined for filters using multiplying digital/analogue convenors (MDAC) as controlling components. The minimisation of the average control error in the case of parameters tuned over a range of values is discussed. High-frequency limitationsof classes ¿ and B filters with VCVS due to the finite gain-bandwidth of op-amp and MDAC nonideality are also derived and compared.