Filter and osilator design using active circuit components

The devices we use in daily life are divided into digital and analog circuit designs. Although the use of digital circuit designs increases day by day, analog circuit designs are needed. The stimuli in nature can be associated with analog signals. Therefore, analog signal processing circuits are needed. The most important circuit structures of analog signal processing circuits are filter and oscillator circuits. In this thesis, new filter and oscillator designs have been realized by using active circuit elements. First of all, the first order allpass filter circuit is presented using the Current Operational Amplifier (COA). This new circuit topology consists of one COA, two resistors and one capacitor. Then, third order quadrature oscillator circuits with two different topologies are presented using the Inverted Current Feedback Operational Amplifier (ICFOA), which is widely used in recent years. The third-order quadrature oscillator structure is constructed by using the second-order low-pass filter using ICFOA and the cascade of the integrator as closed-loop. In this thesis, two all-pass filter and oscillators are applied in different topologies by using Current Differencing Buffered Amplifier (CDBA) element. However, two different second order filter designs are presented using the same topology. The functionality of all presented circuits has been tested using the PSPICE program. It was seen that the simulation results confirmed the theoretical analyzes.