## 1 Introduction  
Active filters and oscillators have received significant attention in analog systems because they are frequently used in electrical and electronic engineering works [1; 2; 3; 4; 5; 6; 7]. The current feedback operational amplifiers (CFOAs) are very attractive elements used for realizing active filters and oscillators. CFOAs have an extended bandwidths and higher slew rates advantage over conventional voltage operational amplifiers [8; 9; 10]. The CFOA has terminal characteristics like positive second generation current-conveyor (CCII+) followed by a voltage buffer (VB) [11; 12]. The most commercial CFOA, such as the AD844 AN from Analog Devices, has obtained the acceptance of researchers as an active building block in analog circuit design [13; 14]. The CFOA differs from the traditional operational amplifier in that the voltage on the non-inverting input terminal is transferred to the inverting input terminal and the inverting input terminal is of low input impedance. Many voltage-mode CFOA-based universal biquadratic filters have been proposed in the literature [14; 15; 16; 17; 18; 19; 20]. These circuit configurations can realize all the standard transfer functions by selecting different input voltages. However, they require the injection of an excitation signal from one terminal of the capacitor in each circuit design and only one/two standard filtering functions at most can be simultaneously obtained in each circuit realization. A multiple inputs and single output universal filter using four CFOAs, five resistors, and two grounded capacitors has been reported in the literature [21]. This circuit provides the features of orthogonal control of resonance angular frequency (\(\omega_{\mathrm{o}}\)) and quality factor (Q), using only grounded capacitors as well as high-input impedance. However, this reported circuit needs to employ four CFOAs and needs a component matching condition for realizing the all-pass filtering function. The configuration in the literature [22] proposed another three-input single-output CFOA-based biquadratic filter. This configuration employs three CFOAs, five resistors, and two grounded capacitors. The circuit also provides the features of orthogonal control of \(\omega_{\mathrm{o}}\) and Q, using only grounded capacitors as well as high-input impedance. However, this circuit still needs a component matching condition for realizing the all-pass filtering function. It is known that a useful feature of the multifunction biquadratic filter is that the low-pass, band-pass, high-pass, and/or band-reject outputs are simultaneously available at various nodes in the circuit. These additional outputs can be used in some systems that employ more than one filter function [23]. Hence, four CFOA-based universal biquadratic filters were proposed in the literature [24]. These proposed configurations can simultaneously realize low-pass, band-pass, and high-pass responses and have several other possible applications such as in crossover networks used in three-way high-fidelity loudspeakers, and phase-locked loop frequency modulation stereo demodulators [25]. Of particular interest here are the voltage-mode CFOA-based multifunction biquadratic filters [26; 27; 28; 29]. Therefore, a voltage-mode non-inverting low-pass (LP), inverting band-pass (IBP), and non-inverting band-reject (BR) filter employing three CFOAs, three resistors, and two grounded capacitors has been proposed in the literature [26] but it does not offer high-input impedance. Another voltage-mode LP, non-inverting band-pass (BP), and non-inverting high-pass (HP) filter employing three CFOAs, four resistors, and three grounded capacitors has been proposed in the literature [27] but it suffers from the drawback of using three capacitors. A high-input impedance voltage-mode LP, IBP, HP, and BR filter employing four CFOAs, four resistors, and two grounded capacitors has been proposed in the literature [28] but it suffers from the drawback of using four CFOAs.