New possibilities in the design of analog integrated circuit with MOS-C realization

In this thesis, MOS-C realization approach in analog integrated circuits is investigated. According to this approach, resistors in a circuit are implemented by MOS transistors. For this purpose, firstly the nonlinearity cancellation techniques in the MOS transistor currents are examined and the relevant equations are presented. Appropriate active elements, namely operational amplifier, operational transresistance amplifier, first generation current conveyor, second generation current conveyor, third generation current conveyor, inverting second generation curret conveyor, differential voltage current conveyor, differential difference current conveyor, for the nonlinearity cancellation techniques are given, also the element representations and the terminal equations are shown. Using the nonlinearity cancellation techniques and above mentioned active elements, two new first order allpass filters are presented. Kerwin-Huelsman-Newcomb, Fleischer-Tow and Tow-Thomas biquads are improved for fully integrable and electronically tunable property. A novel single amplifier biquad is obtained and an oscillator circuit is modified for tunable oscillation frequency. As an application example, fifth order elliptic video filter is given. In all of the above mentioned circuits, the resistors are implemented via MOS transistors and this feature gives them fully integrable property. By changing the gate voltage of the MOS transistor, the circuit parameters have electronically tunable feature. The natural frequency, the quality factor and the gain of the circuits can be changed electronically. The workability of the presented circuits has been verified by PSPICE simulation results.