“…The proposed circuits in [13], [20], [23], [25], [30], [32] ISSN: 2088-8708 are designed for electronic tuning by using a multiplier circuit, but two types of the different active elements have been used. The differentiators and integrators of [14], [21], [22], [28], [40] can be electronically tuned the time constant although they are still sensitive to the temperature. Furthermore, some proposed circuits in [11], [12], [15], [17]- [19], [22], [25], [30], [31], [37] use the floating capacitor that is not suitable for the integrated circuit fabrication.…”