Novel Electronically Controlled Current-Mode Design of a Grounded Capacitance Multiplier

This study introduces a current-mode grounded capacitance multiplier characterized by a straightforward design, electronic adjustability, and compatibility with CMOS technology. The circuit utilizes two operational transconductance amplifiers (OTAs), a current follower (CF), and a single passive capacitor, eliminating the need for matching components. The effective capacitance is electronically regulated with the help of OTA’s bias current. The operation of the active devices in subthreshold mode enables extremely low power consumption of 0.42 µW with a power supply of ±0.75 V. The suggested capacitance multiplier circuit can achieve a multiplication factor of 98.8 and a maximum deviation of 2.8%. The proposed circuit further demonstrates reliable performance across a broad frequency spectrum. Both ideal and non-ideal aspects are examined to assess real-world performance. The theoretical findings are validated through PSPICE simulations with 0.18 µm TSMC CMOS parameters. The proposed topology principle is also experimentally verified using commercially available ICs. The results obtained validate the proposed topology and demonstrate its appropriateness for real-world analog signal-processing applications.