A current mode capacitance multiplier employing a single active element based on Arbel-Goldminz cells for low frequency applications

Abstract

In this work, a capacitor multiplier based on a Multiple Output-Voltage Difference Transconductance Amplifier (MO-VDTA) is built by using Arbel-Goldminz cells with extensive performance analysis. Considering the large chip area occupation of capacitors, capacitor multipliers are one of the most required analog building blocks in most of low frequency applications. In this respect, the obtained capacitor multiplier is tested in a 2nd order low-pass filter by changing the cut-off frequency from 2 kHz to around 12.4 kHz. The multiplication factor (denoted as “k”) of the proposed architecture can be adjusted electronically from 120 to 750 for approximately two decades, while the structure contains only a single active element with a base capacitance. Additionally, the multiplication factor can be safely increased by using additional transconductance stages in the MO-VDTA active block. In the performance analysis, post-layout results are provided in conjunction with process corners, Monte-Carlo analyses and experimental verifications on the basis of commercial off-the-shelf elements such as AD844 and LM13700s.