Voltage-Mode First-Order All-Pass Filter With Active Tuning

Abstract

In this paper, a voltage-mode first-order all-pass filter using three passive components(one capacitor, two resistors) and one active building block (second-generation voltage conveyor)is presented. The proposed design's ideal and non-ideal behaviors are examined to ensure it functionsin real-world environments. The effects of variations in capacitance and temperature on theperformance of the proposed structure are also analyzed and verified through Monte Carlo simulations.The proposed device gains a patented feature of tunability when NMOS transistors replacetwo passive resistors with an active equivalent design. Moreover, a second-order all-pass filteris included to test the design's practical viability. The circuit validation is conducted using 0.18μm CMOS process parameters with a ±0.9 V power supply, using the PSPICE simulation tool,and also validated by experimental setup using IC AD844.