الفهرس 
Chapter 1 Introductionيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The dominating motivation in analog integrated circuits design is small size, low-voltage, and low-power design to be effective for portable systems, where the main voltage supply is a single or multi-cell battery that must maintain for long time. In this area‚ traditional voltage-mode techniques are going to be substituted by the current-mode approach‚ which is able to overcome the limitation of a constant gain-bandwidth product and the trade-off between speed and bandwidth. So the performance is improved in terms of low-voltage characteristics and of slew-rate and bandwidth.
This thesis deals with one of the most powerful block in the area of current mode analog signal processing which is current conveyor.
In this thesis, the basic current conveyor’s principles and some basic modifications of current conveyor are covered. Then, general review for the previous work is presented to the conveyor circuits from the first generation to the recent researches.
Moreover, proposed current conveyors based on TSMC 0.18µm CMOS technology are presented. The proposed circuits’ performance has been investigated by Pspice simulation program. The presented current conveyors are supplied at ± 0.75 V. The Pspice simulations indicate that the proposed circuits present low input impedance port for input current and output voltage (X-port), high input impedance port for voltage mode operation (Y-port), low power operation, accurate voltage and current tracking with low offset, and wide bandwidth.
The first proposed current conveyor is implemented based on a simple rail-to-rail class AB folded cascode CMOS Op-Amp. The first conveyor is employed to implement a four quadrant analog multiplier, which proves the performance of that conveyor.
The second one is a modified version of the first conveyor, in which the input stage is cross-coupled quad cell to enhance the linearity, and the output stage is also enhanced. A square wave oscillator is constructed by the modified conveyor. The applications show the useful of current conveyors in the analog signal processing.
By comparing proposed current conveyors with previous work, it is obvious that the performance of proposed current conveyors is much better than that of previous work in terms of speed‚ bandwidth, and accuracy.