Realization of Resistorless Voltage Mode Universal Filter and Quadrature Oscillator Employing DDTAs with CMOS 180 nm Technology at 0.2V

This paper presents a low-supply-voltage CMOS realization of the Differential Difference Transconductance Amplifier (DDTA). Differential Difference Transconductance Amplifier offers operational complexity with a 0.2 volt supply voltage. The proposed circuit is designed for low-frequency applications in biomedical and sensor applications, and it also consumes 356.66 nW of power. This configuration consists of two DDTAs and two grounded capacitors for a voltage mode universal filter and quadrature oscillator, which are presented in Signal Generation, Audio & Image Processing, Instrumentations, biomedical, and sensor applications. The universal filter presents high impedance at the input and is electronically tunable of the natural frequency in the range of hundreds of Hz. The total harmonic distortion (THD) for the band-pass filter was 0.46% for a 100 mVpp input signal with a frequency of 83.97 Hz. The small modifications in the universal filter structure yield a quadrature oscillator. The condition of oscillations and the frequency of oscillation are electronically controllable. The total harmonic distortion (THD) for a 68.23 Hz oscillation frequency is approximately around 1.16%. The proposed circuits are designed and simulated in a Cadence environment using 180 nm CMOS technology. The CMOS simulation results confirm the performance of the designed universal configuration.