Resistorless OTA-based First order SIMO Universal Filter with High Input Impedance

This article proposes a voltage mode first-order universal filter(UF) designed with a single input multiple output (SIMO) configuration. The filter utilizes Operational Transconductance Amplifiers(OTAs) and grounded-capacitors, ensuring compatibility with integrated circuit fabrication. The design supports electronic tuning of pole frequency, offers high input impedance and simultaneous realization of low pass, high pass and non-inverting all pass responses without requiring the precise matching of components. Comprehensive analysis of nonidealities and parasitic effects confirms the design's robustness, while sensitivity analysis shows unity sensitivity to component variations. Simulated using 90nm CMOS technology with ±0.8V supply voltage, the circuit demonstrates a pole frequency of 105.956 kHz with excellent linearity (THD < 0.68% for LP, < 1.09% for HP configurations).