Two novel universal current-mode filters using unity-gain current followers
(CFs) and voltage followers (VFs) are presented. The first one, employing
three CFs, one VF, two grounded capacitors and two resistors, has two input
s and three outputs. The second one, employing only two CFs, one VF, two gr
ounded capacitors and two resistors, has four inputs and a single output. B
oth proposed circuits offer the following advantageous features: universal
current-mode filter realization from the same configuration, no requirement
s of component matching conditions, employment of two grounded capacitors i
deal for integration, employment of two virtually grounded resistors good f
or voltage control, easy adjustment of omega (0)/Q and omega (0) through se
parate virtually grounded resistors and low active and passive sensitivity
performance.