Current Operational Amplifier Based Voltage-Mode MOS-C All-Pass Filter and Its Application

Abstract

In this work, a novel first order voltage-mode all-pass filter employing single active element named current operational amplifier (COA), two resistors, one capacitor and it's application as sinusoidal oscillator is presented. The resistors are implemented by using MOSFETs, so the resulting MOS-C circuit is suitable for integration and the central frequency of the filter is electronically tunable. Workability of the proposed filter and it's application is validated by PSPICE simulation software using TSMC 0.18 micron CMOS model parameters. Simulation results are in good consistency with theoretical analysis. The proposed circuit features precise frequency tuning, operability at low voltage, low distortion and low phase error.