Voltage differencing buffered amplifier-based electronically tunable grounded capacitance multiplier

A minimal realization of electronically adjustable capacitance multiplication topology with voltage differencing buffered amplifier (VDBA) is proposed. The proposed capacitance multiplier circuit is designed by means of two VDBAs and one floating capacitor. A capacitance multiplication factor is adjusted electronically through the ratio of two transconductances. The effect of the non-ideal gains of the VDBA is also taken into account and carried out. As an analog application example, the proposed capacitance multiplier circuit is utilized in the design of an electronically tunable first-order low-pass filter. PSPICE simulations with TSMC 0.25-µm CMOS technology are included to support the theoretical analysis.